¶1. The Petitioners in this case are various Wisconsin students, parents, teachers, school districts, school board members, citizens, and the president of the Wisconsin Education Association Council (WEAC).1 The Petitioners collec*599tively challenge the constitutionality of the state school finance system under Wis. Stat. ch. 121 and Wis. Stat. §§ 79.10 and 79.14. Two main issues are presented for our review: 1) whether the state school finance system is unconstitutional under Wis. Const, art. X, § 3 — the uniformity clause of the education article; and 2) whether the state school finance system is unconstitutional under Wis. Const, art. I, § 1 — the Equal Protection Clause. The Petitioners contend that the school finance system violates both art. X, § 3 and art. I, § 1 because it fails to equalize access to financial resources among school districts.
¶ 2. In an unpublished decision, the court of appeals upheld the constitutionality of the school finance system. Vincent v. Voight, No. 97-3174, unpublished slip op. (Ct. App. Dec. 23, 1998). The court determined that the current school finance system is not materially different from the system that this court upheld as constitutional in Kukor v. Grover, 148 Wis. 2d 469, 436 N.W.2d 568 (1989).2 Slip op. at 6. We agree *600that the Petitioners have not proved beyond a reasonable doubt that the current state school finance system violates either art. X, § 3 or art. I, § 1 of the Wisconsin Constitution. The present school finance system more effectively equalizes the tax base among districts than the system in place at the time Kukor was decided.
¶ 3. We further hold that Wisconsin students have a fundamental right to an equal opportunity for a *601sound basic education. An equal opportunity for a sound basic education is one that will equip students for their roles as citizens and enable them to succeed economically and personally. The legislature has articulated a standard for equal opportunity for a sound basic education in Wis. Stat. §§ 118.30(lg)(a) and 121.02(L) (1997-98) as the opportunity for students to be proficient in mathematics, science, reading and writing, geography, and history, and for them to receive instruction in the arts and music, vocational training, social sciences, health, physical education and foreign language, in accordance with their age and aptitude.3 An equal opportunity for a sound basic education acknowledges that students and districts are not fungible and takes into account districts with disproportionate numbers of disabled students, economically disadvantaged students, and students with limited English language skills. So long as the legislature is providing sufficient resources so that school districts offer students the equal opportunity for a sound basic education as required by the constitution, the state school finance system will pass constitutional muster.
I
A. The Wisconsin School Finance System
¶ 4. We begin by outlining the constitutional provisions applicable to school finance. Article X of the Wisconsin Constitution establishes the state public school system4 and provides that the school districts *602"shall be as nearly uniform as practicable. . . Wis. Const, art. X, § 3. The constitution also creates a school fund for the "support and maintenance" of schools and libraries. Wis. Const, art. X, § 2. Article X, § 4 allows for the imposition of a local tax on the school districts. It states that the sum to be raised locally must be "not less than one-half the amount received by such town or city respectively for school purposes from the income of the school fund." Wis. Const, art. X, § 4. Section 5 provides for the distribution of the income from the school fund "in some just proportion to the number of children and youth resident therein between the ages of four and twenty years." Wis. Const, art. X, § 5.
¶ 5. From these constitutional provisions, the legislature has developed an elaborate state school finance formula.5 One source of school funding is the property tax, which applies directly to each local district. The other significant source of funding is state aid.6 State aid includes equalization aid, categorical aid, and the school levy tax credit.7 We describe each type of aid in turn.
*603EQUALIZATION AID
¶ 6. According to the Legislative Fiscal Bureau, equalization aid "is intended to ensure that differences in tax rate primarily reflect differences in school district spending levels."8 Wisconsin Legislative Fiscal Bureau, Elementary and Secondary Sch. Aids at 10 (Jan. 1999). Equalization aid is distributed on the basis of a school district's relative fiscal capacity. Id. at 1. The majority of school funds are derived from property taxes. However, since the property tax base differs between districts, the state distributes equalization aid according to the formula set forth in Wis. Stat. § 121.07 (1997 — 98).9 Equalization aid provides each qualifying school district with a guaranteed tax base, thereby *604minimizing differences in the ability of school districts to raise revenue through property tax. Equalization aid compensates any deficiencies in a school district's tax base up to the guaranteed amount provided by the state. In other words, the equalization aid "make[s] up the difference between the district's actual tax base and the statefs] guaranteed tax base." Elementary and Secondary Sch. Aids at 7.
¶ 7. Computation of state equalization aid depends on five factors: a) membership, b) shared cost, c) equalized property valuation, d) guaranteed valuation, and e) the amount of available funding. Elementary and Secondary Sch. Aids at 7. The number of students enrolled in a district determines the district's membership. Wis. Stat. § 121.07(l)(a). Shared cost is the "sum of the net cost of the general fund and the net cost of the debt service fund." § 121.07(6)(a). Shared cost represents those school district expenditures for which the equalization formula provides aid. Elementary and Secondary Sch. Aids at 8. Equalized property valuation is "the full market value of taxable property in the school district as determined by the Department of Revenue (DOR). . .each year." Id. District equalized value (DEV) is the equalized valuation on a per pupil basis. See Elementary and Secondary Sch. Aids at 33. Guaranteed valuation represents a guaranteed tax base. Id. at 10. The state guaranteed valuation (SGV) is "the amount of property tax base support which the state guarantees behind each pupil." Id. at 8. See also § 121.07(7)-(8).
¶ 8. Equalization aid applies at three different district spending levels. District spending levels are defined in terms of shared cost. The first level consists of a primary guaranteed tax base of $2,000,000 per *605pupil for the first $1,000 of shared costs.10 Wis. Stat. § 121.07(6)(b), (c), and (7)(a). The $1,000 is also referred to as the primary cost ceiling. The Legislative Fiscal Bureau further explains:
The first level is for shared costs up to the "primary cost ceiling" of $1,000 per member. The state's sharing of costs at the primary cost ceiling, referred to as "primary shared costs," is calculated using a statutory guaranteed valuation of $2,000,000 per member. State aid at the primary level is based on a comparison between a school district's equalized valuation per member and the primary guaranteed valuation; state aid will equal the amount of costs that would be funded by the missing portion of the guaranteed tax base. Elementary and Secondary Sch. Aids at 8.
Currently, all school districts in the state receive some primary equalization aid. The primary guarantee is protected by a hold harmless provision, which means that negative aids cannot reduce any district's primary aid amount. See id.
¶ 9. The state gives secondary equalization aid to a school district when the district spends at a level between the primary shared cost ceiling and the secondary cost ceiling. Elementary and Secondary Sch. Aids at 8. See also Wis. Stat. § 121.07(6)(d)l-2 and (dg). The 1998-99 secondary cost ceiling was $6,285. Elementary and Secondary Sch. Aids at 8. The amount of aid is *606determined by the ratio of a district's actual per-pupil equalized valuation to the secondary guaranteed valuation. The secondary guaranteed valuation is a variable amount. Id. In 1998-99 it was $676,977. Id.
¶ 10. The third level, or "tertiary shared cost" level, "is that portion of a school district's shared cost which is greater than the secondary ceiling cost per member multiplied by its membership." Wis. Stat. § 121.07(6)(dr). Before the legislature acted in 1995, the state employed a two-tiered system, which was replaced by the current three-tiered system under 1995 Wis. Act. 27. The amount of tertiary aid is deducted from the secondary aid amount if the amount of tertiary aid is a negative number. Elementary and Secondary Sch. Aids at 9. This is referred to as "negative aid." However, when the secondary and tertiary aid equal a negative number, the resulting amount is not deducted from the primary aid. Id. The tertiary guarantee is designed to discourage districts from spending at a level above the ceiling, and to narrow per pupil spending disparities. Id.
¶ 11. Applying these concepts, the amount of aid a district receives at any level may be determined by the following formula:
State aid = 1-DEV/SGV x shared cost11
The general equalization formula to determine the amount of aid a school district receives is:
*607Equalization aid = (1-(DEV¡primary SGV) x primary shared cost) +
(1-(DEVIsecondary SGV) x secondary shared cost) +
(1-(DEV¡tertiary SGV) x tertiary shared cost)
CATEGORICAL AID
¶ 12. There are approximately 25 categorical aid programs.12 The programs are either formula-driven, or they are grant programs. Formula-driven programs give funds to school districts on the basis of the number of students who meet the criteria for the program. Elementary and Secondary Sch. Aids at 14. Grant programs require districts to submit a proposal to receive funds. Id. Categorical aids differ from equalization aid in that they do not depend on the relative *608wealth of a school district. Id. Categorical aids are not calculated into statutory revenue limits.
THE SCHOOL LEVY TAX CREDIT
¶ 13. The school levy tax credit is paid to municipalities, in contrast to equalization aid and categorical aid, which are paid to school districts. Elementary and Secondary Sch. Aids at 1. See also Wis. Stat. §§ 20.835(3)(b), 79.10, 79.14. The tax credit is designed to reduce property taxes. Id. In 1998-99, on a statewide level, the school levy credit reduced the school portion of tax bills by 16.8% on average. Elementary and Secondary Sch. Aids at 29.
¶ 14. In addition to the school levy tax credit, district increases funded by local taxes are limited by a fixed amount, termed a "revenue limit." Wis. Stat. § 121.91. Revenue limits may only be exceeded if residents in a district pass a voter referendum. § 121.91(3). A school district may be penalized if the school district exceeds the maximum allowed revenue under § 121.91. § 121.92.
B. Procedural History
¶ 15. We now turn to an examination of the procedural history of this case. The Plaintiffs initiated this action in October 1995. Thereafter, the president of the Wisconsin Education Association Council (WEAC) and other teachers ("the Intervening Plaintiffs") intervened. The Plaintiffs, Intervening Plaintiffs, and Defendants filed cross-motions for summary judgment on February 24,1997.
*609¶ 16. The Petitioners13 contend that the needs of Wisconsin students are changing and that the school finance system has not kept up with those needs. They contend that the perceived inequities in the system violate the uniformity clause and the Equal Protection Clause, contrary to the Wisconsin Constitution. The inequality stems from a failure "to adequately adjust for the disparity in tax base." (Pl.-Pet'r's Br. at 4.) As a result, property wealth dictates educational opportunity in this state, the Petitioners argue.
¶ 17. According to the Petitioners, categorical aids have been reduced, which "effectively restricts district spending by preventing the school board from compensating for the reduced state aid with additional property tax revenue." (Intervening Pl.-Pet'r's Br. at 12.) This results in school districts shifting funds away from regular programs and into categorical programs. As a result, some districts are unable to retain teaching positions or maintain school facilities. Other districts have cut their offerings in advanced placement or multiple foreign languages. .
¶ 18. The Petitioners further contend that revenue limits prevent school districts from raising necessary funding. For instance, revenue limits prohibit school districts from purchasing and implementing new technology.
¶ 19. Moreover, the Petitioners argue that there has been a significant increase in "high need" students in Wisconsin. High need students include impover*610ished children, disabled children, and children with limited English skills. Additional programs have been mandated by either the state or the federal government for these high need students, but without necessarily increasing funding for the programs.
¶ 20. Finally, the Intervening Plaintiffs-Petitioners contend that charter schools and the Milwaukee Parental School Choice Program pull students out of the public schools. This in turn decreases the number of pupils, or members, in a school district, reducing the amount of funding the district receives.
¶ 21. The circuit court, the Honorable Richard J. Callaway presiding, found that under Kukor, 148 Wis. 2d 469, the school finance system is constitutional and granted the defendants' motion for summary judgment. The court first noted that all children in this state have an equal right to education. However, the Plaintiffs "mistakenly framed the issue as whether the State distributes its school money in a manner which equalizes local budgets rather than whether the children of Wisconsin. . .are receiving the education to which they are entitled." The court then concluded that the Plaintiffs and Intervening Plaintiffs had not overcome the strong presumption of constitutionality that statutes enjoy. See, e.g., United States v. National Dairy Prod. Corp., 372 U.S. 29, 32 (1963).
¶ 22. The school finance system does not violate the uniformity clause of the constitution, the circuit court found, because according to this court's interpretation of the uniformity clause in Kukor, 148 Wis. 2d at 492 (Ceci, J. plurality); 148 Wis. 2d at 514 (Steinmetz, J., concurring), the constitution does not require that the educational opportunities provided by school districts be absolutely equal.
*611¶ 23. The circuit court also determined that the school finance system does not violate equal protection. The court repeatedly noted that the Plaintiffs and Intervening Plaintiffs failed to give virtually any evidence relating to the quality of education students receive in Wisconsin, and therefore, the court could not ascertain whether students are being deprived of their right to an education. The state has significantly increased its total state aid to the public schools, and the increase in state aid outweighs any disproportionate distribution of tax credit to wealthy property owners. The court further recognized that the current system provides schools across the board with more state aid than the system at issue in Kukor. The schools face the same problems that they did when the Kukor court reviewed the system, and the Kukor court was unpersuaded by those facts.
¶ 24. In sum, the circuit court concluded that the Plaintiffs and Intervening Plaintiffs did not demonstrate the school finance system's negative impact on education. Without such evidence, the court had no way to ascertain "the magnitude of any deficiencies in the State's effort to fulfill its duty to provide students with a basic education."
¶ 25. The court of appeals agreed that the plaintiffs did not demonstrate any material difference between the current system and the system at issue in Kukor. Vincent, slip op. at 6. In other words, no significant disparities exist between the aid given under either system. Slip op. at 28-29. Moreover, the court found no evidence of children who do not receive at least a basic education. Slip op. at 32-33. In fact, the court concluded, "the evidence suggests that the state is providing greater aid to school districts than it did at the time Kukor was decided." Slip op. at 33.
*612¶ 26. Judge Dykman concurred in the court of appeals' decision, but noted the record demonstrated "that lower spending school districts are laboring under very difficult conditions." Vincent, slip op. at 35 (Dykman, J., concurring). The concurrence also lamented that Kukor contained no test for the court of appeals to use in assessing the current finance system and that "substantially improved programs are needed in our less affluent school districts." Slip op. at 36.
¶ 27. In part II of this opinion we analyze art. X, § 3 in light of its constitutional history and this court's past precedent. We affirm Kukor, but explain further the Kukor definition of equal opportunity for an education. In parts III and IV we address whether the current school finance system violates art. X, § 3 and art. I, § 1 of the Wisconsin Constitution.
HH HH
¶ 28. We begin by interpreting the uniformity clause in art. X, § 3 of the Wisconsin Constitution, which states that the district schools "shall be as nearly uniform as practicable."14 We interpret constitutional provisions de novo. Thompson v. Craney, 199 Wis. 2d 674, 680, 546 N.W.2d 123 (1996). We benefit, however, *613from the analyses of the circuit court and the court of appeals.
¶ 29. We recognize that "the clear purpose of art. X, § 3, was to compel the exercise of the power to the extent designated." Zweifel v. Joint Dist. No. 1, Belleville, 76 Wis. 2d 648, 658, 251 N.W.2d 822 (1977). It is a "fundamental principle" that the Wisconsin Constitution limits legislative power. Manitowoc v. Manitowoc Rapids, 231 Wis. 94, 97, 285 N.W. 403 (1939). See also State ex rel. Dudgeon v. Levitan, 181 Wis. 326, 339, 193 N.W. 499 (1923); Pauly v. Keebler, 175 Wis. 428, 439, 185 N.W. 554 (1921); Outagamie County v. Zuehlke, 165 Wis. 32, 35, 161 N.W. 6 (1917). In Busé v. Smith, 74 Wis. 2d 550, 564, 247 N.W.2d 141 (1976), we specifically stated that "the search is not for a grant of power to the legislature but for a restriction thereon." Moreover, it is "a limitation upon the broad power of the state to educate its citizens through the establishment and operation of schools. The limitations are precisely stated: District schools, uniformity, and free tuition for certain ages." Zweifel, 76 Wis. 2d at 658. See also Manitowoc, 231 Wis. at 97-98; Zuehlke, 165 Wis. at 35.
¶ 30. Three sources guide our interpretation of a constitutional provision: "the plain meaning of the words in the context used; the constitutional debates and the practices in existence at the time of the writing of the constitution; and the earliest interpretation of the provision by the legislature as manifested in the first law passed following adoption." Id.
¶ 31. The word "uniform" in the context of art. X, § 3 plainly refers to the "character of instruction" provided in the public schools. In T.B. Scott Lumber Co. v. Oneida County and another, 72 Wis. 158, 161, 39 N.W. 343 (1888), this court found that the organization of a *614township school system15 did not violate the uniformity clause under art. X, § 3. By finding the township school system "uniform," this court implied that it did not equate equal acreage with "uniformity." Suzanne M. Steinke, The Exception to the Rule: Wisconsin's Fundamental Right to Education and Public School Financing, 1995 Wis. L. Rev. 1387, 1399 [hereinafter, The Exception to the Rule]. Later, in State ex rel. Zilisch v. Auer, 197 Wis. 284, 290, 221 N.W. 860 (1928), we determined that the uniformity clause in art. X, § 3 related to the "character of instruction" at the public schools after they were established, not the "method of forming school districts," or fixing district boundaries. "Character of instruction" was described as "the training that these schools should give to the future citizens of Wisconsin." Id. These representative cases demonstrate that from our earliest jurisprudence on, we have construed the uniformity clause to relate to the "character of instruction" offered in the public schools, and not the size, boundaries, or composition of the school districts. See also The Exception to the Rule, 1995 Wis. L. Rev. at 1400.
¶ 32. The practices in existence around the time of the constitutional conventions further guide our interpretation of Wis. Const, art. X, § 3. Before the mid — 1800's, elementary and secondary schools were generally privately funded. Erik LeRoy, The Egalitarian Roots of the Education Article of the Wisconsin Constitution: Old History, New Interpretation, Busé v. Smith Criticized, 1981 Wis. L. Rev. 1325, 1344 [hereinafter, Egalitarian Roots]. See also The Exception to the *615Rule, 1995 Wis. L. Rev. at 1391. The territorial government in 1836 created a "district school" system that was financed partially by taxes, but still in large part by private subscription. Egalitarian Roots, 1981 Wis. L. Rev. at 1344-45.
¶ 33. Several factors produced an "impetus" for free public school education in Wisconsin. Egalitarian Roots, 1981 Wis. L. Rev. at 1347. First, some viewed public schools as an opportunity to eliminate distinctions between the wealthy and the poor.16 Id. at 1346. Others viewed public schools as a way to integrate the swell of new immigrants with East Coast "transplants." Id. at 1347. Finally, others simply wanted to use state funds to "to pay for education." Id. at 1348.
¶ 34. It appears that by the time of the 1846 constitutional convention, there was general support for a constitutional provision on education. Egalitarian Roots, 1981 Wis. L. Rev. at 1348 and n.101. The 1846 constitutional convention manifested its support for education by devoting 500,000 acres of land, which the federal government was to give to Wisconsin upon attaining statehood. Id. at 1349. Unfortunately, however, no debates ensued relating to the draft of art. X, § 3 at either the 1846 or 1848 constitutional conventions because the provision was wholly uncontroversial. Id. at 1350.
¶ 35. Finally, we examine the early state statutes on school finance. The state laws of 1848 contained a number of statutory provisions relating to the public schools. The most comprehensive statute on public schools included a detailed section on local *616taxes17 and a section on the distribution of income of *617the school fund. "An Act in Relation to Public Schools," Laws of 1848, p. 240-41, 243. Significantly, Section 91 of the statute required each town receiving state funds to match at least half of the amount donated by the state. Section 92 set the property tax at "two and a half mills on each dollar." Section 93 provided for an additional tax that could be raised after a vote was taken to fund teachers' wages and expenses. The school fund provision stated that towns would receive interest from the school fund "in proportion to the number of children in such town-" Section 104, Distribution of Income of the School Fund, Laws of 1848, p. 243.
¶ 36. The plain meaning, the practices around the time of the constitutional convention, and the early statutes all indicate that art. X, § 3 was intended to refer to the character of the instruction given at the public schools.
¶ 37. We now turn to this court's more recent precedent regarding school finance. This court has directly examined the constitutionality of the state school finance system twice in the last 25 years. At issue in Busé, 74 Wis. 2d at 556, were two statutes that created negative aid for certain school districts, or reduced the positive aid those districts could have received. The plaintiffs, the negative aid school districts and property taxpayers residing in the negative aid school districts, argued that the negative aid statutes were unconstitutional. Their main argument was *618that the statutory negative aid provisions violated the rule of uniform taxation, articulated in art. VIII, § 1 of the Wisconsin Constitution. Busé, 74 Wis. 2d at 554. Additionally, the court addressed whether negative aid was unconstitutional under art. X, §§ 3 and 4 and art. I, § 1 of the Wisconsin Constitution. Id. at 562.
¶ 38. The court first examined whether the statutes violated the uniformity clause of Wis. Const, art. X, § 3. The court specifically considered whether art. X, § 3 requires the legislature "to provide an equal opportunity for education for all school children in the state." Busé, 74 Wis. 2d at 562. The court recognized that while the United States Constitution does not require the establishment of schools, San Antonio Indep. Sch. Dist. v. Rodriguez, 411 U.S. 1 (1973), the Wisconsin Constitution does contain that requirement. Busé, 74 Wis. 2d at 564 (quoting Wis. Const, art. X, § 3). Besides establishing the public schools, art. X, § 3 also states that the public schools must be "as nearly uniform as practicable" and that children in the state may attend the public schools without charge. Id. at 565.
¶ 39. Having set forth the pertinent constitutional provisions, the court held the framers of the constitution intended the phrase "as nearly uniform as practicable" to refer to the "character of instruction" at the district schools. Id. at 566 (quoting State ex rel. Zilisch v. Auer, 197 Wis. 284, 289-90, 221 N.W. 860, 223 N.W. 123 (1928)). The court further stated that "[e]quality of opportunity for education is equated with the right of all school children to attend a public school free of charge...," id. at 565, and equal opportunity for education is a fundamental right. Id. at 567. However, the court concluded that according to the plain meaning of art. X, § 3 and constitutional history, art. X, § 3 *619does not require educational opportunity to be absolutely uniform. Id. at 568.
¶ 40. With regard to art. X, § 4 of the Wisconsin Constitution, the court examined whether local district control of funding was, in some measure, required by the constitution. Busé, 74 Wis. 2d at 570. The court again carefully examined the language of the constitution, the constitutional debates, and the early legislative enactments to determine that "[l]ocal districts retain the control to provide educational opportunities over and above those required by the state and they retain the power to raise and spend revenue '. . .for the support of common schools therein.Id. at 570-72.
¶ 41. The court then found the negative aid provisions unconstitutional in light of the uniform tax rule in art. VIII, § 1 of the Wisconsin Constitution. The court set forth the limitations on the power to tax, noting that "the purpose of [a] tax must be one which pertains to the public purpose of the district within which the tax is to be levied and raised." Id. at 577. The state does not have the power to tax a local entity " 'for a purely local purpose.'" Id. at 576 (quoting Thomas M. Cooley, Law of Taxation, § 86, pp. 211, 212 (1924)). As such, the court concluded, "the state cannot compel one school district to levy and collect a tax for the direct benefit of other school districts, or for the sole benefit of the state." Id. at 579.
¶ 42. Finally, the court examined whether the negative aid provisions violated equal protection and due process. Because the court held that equal educational opportunity is a fundamental right, the court applied the strict scrutiny test to its equal protection analysis. Id. at 580. The court then concluded that the negative aid provisions survived strict scrutiny. Id.
*620¶ 43. The concurrence viewed negative aid as a state tax. Busé, 74 Wis. 2d at 581 (Robert W. Hansen, J., concurring). However, the concurrence agreed with the majority that a municipality cannot be forced to assume obligations that it does not ordinarily have. Id. (quoting Lund v. Chippewa County, 93 Wis. 640, 648-49, 67 N.W. 927 (1896)).
¶ 44. The dissent disagreed that negative aid violated the uniform taxation rule. Busé, 74 Wis. 2d at 583 (Abrahamson, J., dissenting). The dissent first noted that it felt the majority had not "accorded this statute the proper presumption of constitutionality." Id. at 584. Moreover, the dissent argued it was "not clear beyond reasonable question that the statute conflicts with the constitution," and when in doubt, a court must " 'favor. . .the validity of the act.'" Id. (quoting State ex rel. New Richmond v. Davidson, 114 Wis. 563, 579-80, 88 N.W. 596, 90 N.W. 1067 (1902)).
¶ 45. The dissent articulated the issue before the court as "whether the 'negative aid' statute violates the public purpose doctrine. . . ." Busé, 74 Wis. 2d at 589. The dissent found that negative aid "applies across the state to all school districts," and "[n]o one school district is singled out to support another school district or state education." Id. at 594. Moreover, the dissent felt that negative aid should not be invalidated just because some, but not all, districts have to pay it. Id. The dissent concluded that the negative aid provisions were consistent with precedent. Id. at 594-95.
¶ 46. More recently, in Kukor v. Grover, the plurality and concurrence agreed that under art. X, § 3 of the Wisconsin Constitution each student is guaranteed a basic education.18 148 Wis. 2d at 503 (Ceci, J., plural*621ity); id. at 514 (Steinmetz, J., concurring). The plurality and concurrence further agreed that education does not have to be absolutely uniform to satisfy art. X, § 3.19 Id. at 487 (Ceci, J., plurality); id. at 514 (Steinmetz, J., concurring). Second, the plurality and concurrence held that the legislature's fiscal decisions regarding education are entitled to great deference. Id. at 502-03 (Ceci, J., plurality); id. at 512 (Steinmetz, J., concurring). Third, the plurality and concurrence held that it is not necessary to analyze the school funding system under strict scrutiny, because equal allocation of state resources is not a fundamental right.20 Id. at 498 (Ceci, J., plurality); id. at 5.13 (Steinmetz, J., concurring).
¶ 47. The dissent characterized the state school finance system as "fundamentally flawed" because the state, according to the dissent, did not take educational need into account when distributing funds. Kukor, 148 Wis. 2d at 516 (Bablitch, J., dissenting). The dissent *622noted that "character of instruction" had been defined by this court as " 'services, procedures, opportunities or rules' provided in district schools." Id. at 520 (quoting Zweifel v. Joint Dist. No. 1, Belleville, 76 Wis. 2d 648, 653, 251 N.W.2d 822 (1977)). The dissent then pointed to the circuit court's findings, which indicated the failure of the school finance system. Id. at 522-24. In particular, the dissent criticized the finance system's method of funding "special needs" programs, leaving school districts with little choice but to draw funds from "regular" programs to be used for "special needs." Id. at 525. The dissent felt that the evidence demonstrated the finance system's failure to provide children with "a uniform opportunity to become an educated person." Id. at 526.
¶ 48. Our decision in Kukor laid the foundation for the right that we explain today. Recently, a number of states considering the constitutionality of school finance systems have turned toward the notion of educational adequacy as a better approach than previous educational equality analyses. See, e.g., McDuffy v. Secretary of the Executive Office of Educ. and others, 615 N.E.2d 516, 554 (Mass. 1993) (quoting Rose v. Council for Better Educ., Inc., 790 S.W.2d 186, 212 (Ky. 1989)); Pauley v. Kelly, 255 S.E.2d 859, 877 (W. Va. 1979). The adequacy approach to school finance refers to an examination of "the quality of the educational services delivered to children in disadvantaged dis-tricts_" Peter Enrich, Leaving Equality Behind: New Directions in School Finance Reform, 48 Vand. L. Rev. 101, 109 (1995) [hereinafter, Leaving Equality Behind].
¶ 49. Courts have turned toward adequacy as an alternative way to analyze school finance systems because previous decisions centered on equality have *623not lessened the disparity between school districts. Leaving Equality Behind, 48 Vand. L. Rev. at 102-03. Focusing on adequacy, it is claimed, has a number of benefits. Among other benefits, the adequacy approach is "grounded in broadly shared societal values concerning the importance of education and the obligation to provide for the basic needs of society's least advantaged." Id. at 170. The adequacy approach also may be appealing because it does not threaten to lower the level of achievement in some districts in an effort to create equality. Id.
¶ 50. Under the adequacy approach, a state generally lists the types of knowledge that a child should possess to guide a legislature in fulfilling its constitutional obligations. For example, Massachusetts articulated the following guidelines:
An educated child must possess "at least the seven following capabilities: (i) sufficient oral and written communication skills to enable students to function in a complex and rapidly changing civilization; (ii) sufficient knowledge of economic, social, and political systems to enable students to make informed choices; (iii) sufficient understanding of governmental processes to enable the student to understand the issues that affect his or her community, state, and nation; (iv) sufficient self-knowledge and knowledge of his or her mental and physical wellness; (v) sufficient grounding in the arts to enable each student to appreciate his or her cultural and historical heritage; (vi) sufficient training or preparation for advanced training in either academic or vocational fields so as to enable each child to choose and pursue life work intelligently; and (vii) sufficient level of academic or vocational skills to enable public school students to compete favorably with *624their counterparts in surrounding states, in academics or in the job market."
McDuffy, 615 N.E.2d at 554 (quoting Rose, 790 S.W.2d at 212). This type of standard articulates the content of an adequate education. Leaving Equality Behind, 48 Vand. L. Rev. at 176. Courts that have used this approach do not attempt to "displace the legislative function of identifying realistic parameters for the state's ambitions, but rather [attempt] to serve as a goad or as a backstop to the legislature's accomplishment of that task." Id. In Massachusetts, it was expected that limited judicial intervention would likely be "quite productive." Id.
¶ 51. An equal opportunity for a sound basic education is one that will equip students for their roles as citizens and enable them to succeed economically and personally. The legislature has articulated a standard for equal opportunity for a sound basic education in Wis. Stat. §§ 118.30(lg)(a) and 121.02(L). Section 118.30(lg)(a) states that "each school board shall adopt pupil academic standards in mathematics, science, reading and writing, geography and history." Section 121.02(L) requires that "each school board shall.. .provide instruction" in several subjects, according to school grades.
¶ 52. By grounding the standard in statutes, we reiterate our position in Kukor, 148 Wis. 2d at 503, 505 n.14, wherein we stated that we defer to the legislature because it "is uniquely equipped to evaluate and respond to such questions of public policy...." As such, we defer here to the legislature's wisdom in choosing *625which core subjects21 should be involved in providing an equal opportunity for a sound basic education.22
¶ 53. Further, we note that the reason for articulating the standard in terms of equality and adequacy is to guarantee "that each district can provide its students with an acceptable basic level of educational servicesLeaving Equality Behind, 48 Vand. L. Rev. at 112. The objective is to adopt a standard that will "equaliz[e] outcomes, not merely inputs." Id. at 151.
I — I I — I I — I
¶ 54. We now consider the Petitioners' argument that the statutory school finance system set forth in Wis. Stat. ch. 121, and Wis. Stat. §§ 79.10 and 79.14, lacks uniformity under art. X, § 3 of the Wisconsin Constitution. A party challenging a statute must prove that the statute is unconstitutional beyond a reasonable doubt. Norquist v. Zeuske, 211 Wis. 2d 241, 250, 564 *626N.W.2d 748 (1997). "Constitutional challenges to a statute must overcome a strong presumption of constitutionality," and the presumption of constitutionality is greatest for tax statutes. Id. We make every effort to construe a statute consistent with the constitution. Id. We conclude the Petitioners have not proved beyond a reasonable doubt that the statutory school finance system violates art. X, § 3. The state adequately funds each school district to provide for a basic education, and any disparity between districts is a result of district revenue-raising capacity above the state's guaranteed tax base. The right to an equal opportunity for a sound basic education has not been shown to be violated by the present school finance system.
¶ 55. We begin by briefly summarizing the Petitioners' arguments relating to their challenge under art. X, § 3 of the Wisconsin Constitution. Both the Plaintiffs-Petitioners and the Intervening Plaintiffs-Petitioners argue that the school finance system fails because, they contend, the state does not equalize financial resources between school districts. (Pl.-Pet'r's Br. at 41; Intervening Pl.-Pet'r's Br. at 33.) The Plaintiffs-Petitioners specifically argue that the Legislature should "eliminate the tax base disparities from the system so districts that tax the same (at whatever level they choose), spend the same." (Pl.-Pet'r's Br. at 71.)
¶ 56. The Intervening Plaintiffs-Petitioners argue that the state should create a school finance system that "recognizes, rather than ignores, differing needs of both property-poor districts and high needs students." (Intervening Pl.-Pet'r's Br. at 34.) Essentially, the Intervening Plaintiffs-Petitioners would like the state school financing system to adjust the financial resources distributed to school districts to take into account the cost of educating high need students. *627(Intervening Pl.-Pet'r's Br. at 35.) The Intervening Plaintiffs-Petitioners also would like the state to formulate objective standards to measure whether students are receiving at least a basic education. (Intervening Pl.-Pet'r's Br. at 34.)
¶ 57. Historically, this court has held that disparity in the revenue-raising capacity of a school district does not constitute a violation of the uniformity clause. As we stated earlier, in Zilisch, 197 Wis. at 289, we considered whether the phrase, "as nearly uniform as practicable," referred to the method of establishing school districts, or to maintaining schools after the districts were established. The court looked to the language of art. X, § 3, which refers to "the establishment of district schools," for guidance. Id. This language revealed that the framers applied the uniformity clause to the schools themselves, not to the creation of the school districts. Id. at 290. The court explained that the provision spoke to "the character of instruction that should be given in those schools after the districts were formed, — with the training that these schools should give to the future citizens of Wisconsin." Id.
¶ 58. Similarly, in Larson v. State Appeal Bd., 56 Wis. 2d 823, 827-28, 202 N.W.2d 920 (1973), this court again held that art. X, § 3 of the Wisconsin Constitution applies to the "character of instruction" in schools, not the nature of the boundaries between school districts. The appellant in Larson set forth evidence relating to the equalized valuations, the number of students, and the size of the Watertown and Johnson Creek school districts. Id. at 826-27. The court refused to apply an analysis under Wis. Const, art. X, § 3 because the court found that those facts did not pertain to the character of instruction in the districts. Id. at *628828. Larson reaffirmed that this court does not review the composition of school districts under the guise of an art. X, § 3 analysis.
¶ 59. We find this conclusion to be very significant. The Petitioners argue that some school districts have low property values and therefore cannot raise as much local revenue as other districts. However, according to a careful reading of Zilisch, the constitution does not require districts to have uniform revenue-raising capacity. The Zilisch court stated that districts are not required to have uniform boundaries, or to be established in a uniform manner. Zilisch, 197 Wis. at 290. See also Joint Sch. Dist. v. Sosalla, 3 Wis. 2d 410, 420, 88 N.W.2d 357 (1958). If the framers of the state constitution did not intend the districts' boundaries or method of establishment to be uniform, then surely the framers could not have envisioned the districts' taxing capacity to be uniform, since taxing ability and boundaries are interrelated.
¶ 60. Moreover, the constitution only requires that each child receive an equal opportunity for a sound basic education. Busé recognized that children have a fundamental right to an "equal opportunity for education." See Busé, 74 Wis. 2d at 567. We have repeatedly stated this proposition, both before and after our pronouncement in Busé.
¶ 61. First, in State ex rel. Comstock v. Joint Sch. Dist., 65 Wis. 631, 636-37, 27 N.W. 829 (1886), we stated that "when the legislature has provided for each such child the privileges of a district school, which he or she may freely enjoy, the constitutional requirement in that behalf is complied with." Later, in Davis v. Grover, 166 Wis. 2d 501, 539, 480 N.W.2d 460 (1992), we held:
*629"[t]he uniformity clause clearly was intended to assure certain minimal educational opportunities for the children of Wisconsin.... [T]he uniformity clause requires the legislature to provide the opportunity for all children in Wisconsin to receive a free uniform basic education." In Jackson v. Benson, 218 Wis. 2d 835, 894-95, 578 N.W.2d 602 (1998), this court most recently recognized that "art. X, § 3 provides not a ceiling but a floor upon which the legislature can build additional opportunities...."
¶ 62. A review of other provisions in art. X of the Wisconsin Constitution is further helpful in ascertaining the framers' intent in drafting art. X, § 3. Article X, § 5 is the one constitutional provision that allocates state funds for the public school districts. It states that income from the school fund is to be distributed "in some just proportion to the number of children and youth resident therein between the ages of four and twenty years...." This provision articulates the extent of the state's funding obligation to the school districts: to provide funding on a per-pupil basis. The plain meaning of the provision supports this view — the framers phrased their directions in purely mathematical terms such as "proportion" and "number." The provision does not include language from which we could infer that certain children were to be allocated more funding than others based on subjective need alone.
¶ 63. An analysis of Wis. Const, art. X, § 4 further supports our conclusion. Article X, § 4 requires towns and cities to raise a tax to support the schools located within that area. Wis. Const, art. X, § 4. In Busé, 74 Wis. 2d at 571, we recognized the importance of local control under art. X, § 4. We quoted Experience Estabrook, the Chairman of the Constitutional Committee on Education and School Funds during the *630second Wisconsin Constitutional Convention, who argued that local funds should support local schools so that all citizens, wealthy or poor, would have an "adequate interest" in their public schools. We find his language worth repeating:
If a sufficient sum was not contributed by the school fund, the towns should have power to raise more. This provision was directly for the advantage of the poor.... [A] poor man with a family of children, and no fancy lots to dispose of, could understand the advantage. Experience had shown that if nothing was contributed by the town, the common schools languished, and select schools rose on their ruins. The school fund of Connecticut was so large as to be sufficient to defray the expenses of the education of every child within the limits of the state. Yet there, until a year or two, the district school-system had declined. No adequate interest was felt by the people, in common schools, unless they contributed to their support. To obviate this danger, the committee had inserted the section.
Busé, 74 Wis. 2d at 570-71 (quoting Experience Estabrook, Journal and Debates Constitutional Convention 1847-48, p. 335). Estabrook's comments on art. X, § 4 demonstrate that above the constitutionally mandated state per-pupil expenditures, the framers intended local government to contribute a significant amount to school districts. More importantly, Estabrook's comments suggest that local school districts may vary in the amount they tax and spend on their districts.
¶ 64. Other jurisdictions have also upheld their school finance systems on the basis that the state provided for a basic level of education. The Minnesota Supreme Court recently interpreted the phrase, "general and uniform system of public schools," contained *631in the education clause of the Minnesota Constitution, and found that it did not mean" 'identical'" or" 'nearly identical.'" Skeen v. State, 505 N.W.2d 299, 302, 311 (Minn. 1993). The Minnesota school finance system was constitutional, the court determined, because the evidence did not establish "that the basic system is inadequate or that the 'general and uniform' requirement somehow implies full equalization of local referendum levies." Id. at 312. The court further stated that the inequities in the system did not "rise to the level of a constitutional violation." Id. Most significantly, the court recognized that the system was constitutional because it continued to "meet the basic educational needs of all districts." Id.
¶ 65. The Virginia Supreme Court, in examining the education article of the Virginia Constitution, held that it does not require " 'substantial equality' in spending or programs among or within the school divisions in the Commonwealth." Scott v. Commonwealth, 443 S.E.2d 138, 142 (Va. 1994).
¶ 66. Other courts have examined whether the state funds each district enough to fulfill state minimum requirements. The Oregon Supreme Court found compliance under the language of the Oregon Constitution "if the state requires and provides for a minimum of educational opportunities in the district and permits the districts to exercise local control over what they desire, and can furnish, over the minimum." Olsen v. State, 554 P.2d 139, 148 (Or. 1976). Noting that it did not necessarily find the school finance system "desirable," the court nevertheless held that the system was constitutional.
¶ 67. Further, the Colorado Supreme Court cautioned that the uniformity provision in the Education Clause of the Colorado Constitution did "not prevent a *632local school district from providing additional educational opportunities beyond" the constitutional standard. Lujan v. Colorado State Bd. of Educ., 649 P.2d 1005, 1025 (Colo. 1982). Moreover, the court held that the uniformity provision did not require identical per-pupil expenditures among school districts. Id.
¶ 68. The cases from other jurisdictions support our conclusion that the uniformity clause under Wis. Const, art. X, § 3 does not require absolute uniformity in either educational offerings or per-pupil expenditures among school districts. The cases cited above also demonstrate that a school finance system that uniformly funds school districts to provide a basic level of education is constitutional.
¶ 69. We now turn to the evidence presented in this case. The legislature is entitled to deference in its "legislative policy involving fiscal-educational decisions." Kukor, 148 Wis. 2d at 503 (quoting Busé, 74 Wis. 2d at 566). In Busé, 74 Wis. 2d at 566, we explained that the legislature "determined what uniformity [is] 'practicable.'" We uphold a circuit court's findings of evidentiary or historical fact unless they are clearly erroneous. Treiber v. Knoll, 135 Wis. 2d 58, 64, 398 N.W.2d 756 (1987). The Petitioners made a voluminous record, submitting numerous affidavits, depositions, and other materials. We have carefully perused the record made by the Petitioners, and yet we cannot conclude that they have proved the school finance system is unconstitutional beyond a reasonable doubt.
¶ 70. The Plaintiffs-Petitioners attempt to demonstrate that some districts "are able to provide more opportunities" in their course offerings and technology than other districts. (Pl.-Pet'r's Br. at 50, *633quoting Deputy State Superintendent Steven Dold's deposition). They also attempt to demonstrate that some districts maintain better facilities, textbooks, and a larger teaching staff. Finally, they attempt to provide statistical and financial evidence showing differences in equalized valuations between districts. They then cite to case law from Arizona, Ohio, and Vermont, invalidating school finance systems based on financial differences among the school districts in those states. Roosevelt Elementary Sch. Dist. Number 66 v. Bishop, 877 P.2d 806 (Ariz. 1994); DeRolph v. State of Ohio, 677 N.E.2d 733 (Ohio 1997) (plurality opinion); Brigham v. State of Vermont, 692 A.2d 384 (Vt. 1997).
¶ 71. The Petitioners' evidence, however meticulously gathered, fails to demonstrate that any children lack a basic education in any school district. Merely showing disparity of the financial resources among school districts is not enough in this state to prove a lack of equal opportunity for a sound basic education. As we have discussed above, Wisconsin requires districts to fulfil a constitutional minimum educational offering, not a maximum.
¶ 72. While we recognize that the Petitioners have gathered qualitative evidence pertaining to the deteriorating school facilities, limited curricula, and lack of computer technology of some "property poor" school districts, we agree with the Respondents that evidence of the elimination or reduction of certain advanced or elective courses from some districts does not mean that those school districts fail to offer a basic education. (Resp't's Br. at 71-72.) We also strongly agree with the circuit court that the evidence fails to show that the actual basic education being received by the students attending these school districts is inferior to that of the students in the "property rich" school *634districts. There is no evidence, as the circuit court noted, of poor standardized test scores, college entrance rates, or the like. As we have stated, what is required is an equal opportunity for a sound basic education.
¶ 73. Moreover, the present school finance system more effectively equalizes the tax base among districts than the system did at the time Kukor was decided. At the time of the Kukor decision, the system had only two levels of shared cost. Kukor, 148 Wis. 2d at 476-77. The present system now includes a tertiary level of shared cost. The effect of the tertiary level of shared cost has been to redistribute funds to districts spending less, which are those with lower property values. As such, the present system does more to equalize values between districts than the system found constitutional in Kukor did.
¶ 74. State funding has also significantly increased.23 Kukor was based on figures compiled for the 1985-86 school year. Kukor, 148 Wis. 2d at 475 nn.1-2. In 1985-86, the state distributed approximately $1.142 billion in state aid. Kukor, 148 Wis. 2d at n.2 (citing Basic Facts (1986-87), Wisconsin Depart*635ment of Public Instruction at A-6, A-7). By 1997-98, in comparison, the state appropriated approximately $3,804 billion. Elementary and Secondary Sch. Aids at 4, Table 3. Between 1987 and 1998, state aid increased by at least 4.9% every fiscal year, and often much more. Id. For instance, from the 1995-96 fiscal year to the 1996-97 fiscal year, state aid increased by 31.8%.24 Id. In contrast, the Consumer Price Index only reflected increases between 2.3% and 5.4% per year. Id.
¶ 75. The Petitioners also contend that the statutory revenue limits are unconstitutional under art. X, § 3. In particular, the Intervening Plaintiffs-Petitioners argue that revenue limits most severely affect school districts with decreasing student populations, or those with many high needs students. (Intervening Pl.Pet'r's Br. at 47.)
¶ 76. We do not agree that revenue limits adversely affect the constitutionality of the school finance system. Revenue limits were included in the 1848 statutes, as we noted earlier. Revenue limits do not absolutely bar school districts from increased spending — they merely require a voter referendum to do so. Moreover, Wis. Stat. § 121.91(4)(f) and (6), as created by 1997 Wis. Act 27, §§ 2902v and 2903g, minimize the impact of revenue limits on school districts with declining enrollments by adjusting the method for counting pupils. Finally, revenue limits were intended to provide property tax relief, and actually have an equalizing effect, because districts that spend less can increase their spending by a greater percentage without first seeking a referendum.
¶ 77. Finally, we note that the cases cited by the Plaintiffs-Petitioners are distinguishable on the facts. *636Brigham is distinguishable because the Vermont Constitution does not contain a provision requiring local funding of school districts. Brigham, 692 A.2d at 392. In DeRolph, 677 N.E.2d at 742-745, the Ohio Supreme Court concluded that many districts in the Ohio public school system were wholly unable to provide the basic resources necessary to educate the students, and therefore, the finance system was in violation of the Ohio Constitution. This is not the case in Wisconsin where the basic resources are being provided. The school finance system at issue in Roosevelt relied heavily on local property taxation and "only partial attempts at equalization." Roosevelt, 877 P.2d at 815. Again, the state funds two-thirds of the school districts' expenditures in Wisconsin and employs three levels of equalization aid. Certainly, this is not heavy reliance on local property taxation or a half-hearted attempt at equalization.
¶ 78. In sum, we conclude the Petitioners have not proved beyond a reasonable doubt that the statutory school finance system violates art. X, § 3. The state adequately funds each school district to provide for a basic education, and any disparity between districts is a result of district revenue-raising capacity above the state's guaranteed tax base. The right to an equal opportunity for a sound basic education has not been shown to be violated by the current school finance system.
IV
¶ 79. We now address whether the current school finance system violates equal protection under art. I, *637§ 1 of the Wisconsin Constitution.25 First, we must determine whether to apply a strict scrutiny review or a rational basis review. The Petitioners urge us to apply a strict scrutiny standard of review.
¶ 80. Equal protection guarantees the "right to be free from invidious discrimination in statutory classifications and other governmental activity."26 Jackson, 218 Wis. 2d at 901 (quoting Harris v. McRae, 448 U.S. 297, 322 (1980)). We apply a strict scrutiny review of a statute when the legislative classification interferes with a fundamental right or is created on the basis of a suspect criterion. State v. Annala, 168 Wis. 2d 453, 468, 484 N.W.2d 138 (1992). If a fundamental right or a suspect class is not involved, then a court reviews whether the statute's classification "rationally furthers a purpose identified by the legislature." Id. Fundamental rights are based on the Constitution either explicitly or implicitly. State v. Martin, 191 Wis. 2d 646, 652, 530 N.W.2d 420 (Ct. App. 1995) (citing San Antonio Indep. Sch. Dist. v. Rodriguez, 411 U.S. 1, 33 (1973)).
*638¶ 81. We acknowledge that Wisconsin children have a fundamental right to an equal opportunity for a sound basic education, and that right is based on art. X, § 3 of the Wisconsin Constitution.27 Kukor, 148 Wis. 2d at 496 (quoting Busé, 74 Wis. 2d at 567). However, in San Antonio Independent School District v. Rodriguez, 411 U.S. 1, 24 (1973), reh'g denied, 411 U.S. 959 (1973), the United States Supreme Court held that the Equal Protection Clause does not require "absolute equality or precisely equal advantages" on the basis of wealth. We also have stated that while the right to an equal opportunity for education is fundamental in Wisconsin, absolute equality in per-pupil expenditures is not mandated. Kukor, 148 Wis. 2d at 496.
¶ 82. The Petitioners argue that we should review their equal protection claim relating to financial disparities between districts under strict scrutiny. They argue that since this court has recognized the equal opportunity for education as a fundamental right, strict scrutiny applies.
¶ 83. We carefully distinguish between the fundamental right to an equal opportunity for a sound basic education under art. X, § 3 and the wealth-based arguments the Petitioners make. In other words, the fundamental right to an equal opportunity for a sound basic education does not rest on any classification based on wealth. In Kukor we addressed a similar argument. Citing Rodriguez, we concluded that a rational basis standard should be applied "because the rights at issue in the case before the court are premised *639upon spending disparities and not upon a complete denial of educational opportunity within the scope of art. X."28 Kukor, 148 Wis. 2d at 498. See also Skeen, 505 N.W.2d at 316-17 (citing our approach in Kukor with approval). Since the Petitioners' argument rests on wealth-based classifications and not classifications based on art. X, § 3, we apply the rational basis test.
¶ 84. Under the rational basis test, we give great deference to legislative classifications. Tomczak v. Bailey, 218 Wis. 2d 245, 264, 578 N.W.2d 166 (1998). We must " 'locate or. . .construct, if possible, a rationale that might have influenced the legislature and that reasonably upholds the legislative determination.'" Id. (quoting Sambs v. City of Brookfield, 97 Wis. 2d 356, 371, 293 N.W.2d 504 (1980)).
¶ 85. The legislative classifications set forth in Wis. Stat. ch. 121 are rationally related to the purpose of educating Wisconsin's children. The school financing system provides all school districts with a guaranteed tax base. Moreover, the three-tiered shared cost system, which was implemented after Kukor was decided, *640is specifically designed to narrow per pupil spending disparities between districts. The school financing system seeks to equalize the tax base, not rate, of the school districts. Elementary and Secondary Sch. Aids at 10. Arguably, the system of taxation may actually penalize wealthier school districts because it is designed to tax districts that spend at a higher level. See id. (stating that "[a] school district that spends at a higher per pupil level than another will continue to face a higher tax rate unless the district is not subject to the formula because its local tax base exceeds the state's guaranteed tax base.") As such, the three-tiered classification system is rationally related to the legitimate governmental end of providing an equal opportunity for a sound basic education.
¶ 86. Finally, the legislative classifications set forth in Wis. Stat. §§ 121.91 and 121.92 relating to revenue limitations pass the rational basis test. We agree with the Respondents that revenue limitations "serve the legitimate state purpose of reducing the risk that local school boards would use the additional state aid to increase local spending by keeping tax rates as high as they had been before the infusion of additional state aid," instead of replacing local property taxes. (Resp't's Br. at 85.)
V
¶ 87. A majority of this court holds that Wisconsin students have a fundamental right to an equal opportunity for a sound basic education. An equal opportunity for a sound basic education is one that will equip students for their roles as citizens and enable them to succeed economically and personally. The legislature has articulated a standard for equal *641opportunity for a sound basic education in Wis. Stat. §§ 118.30(lg)(a) and 121.02(L) as the opportunity for students to be proficient in mathematics, science, reading and writing, geography, and history, and to receive instruction in the arts and music, vocational training, social sciences, health, physical education and foreign language, in accordance with their age and aptitude. An equal opportunity for a sound basic education acknowledges that students and districts are not fungible and takes into account districts with disproportionate numbers of disabled students, economically disadvantaged students, and students with limited English language skills. So long as the legislature is providing sufficient resources so that school districts offer students the equal opportunity for a sound basic education as required by the constitution, the state school finance system will pass constitutional muster.
¶ 88. We conclude that the school finance system articulated in Wis. Stat. ch. 121 is constitutional under both art. X, § 3 and art. I, § 1 of the Wisconsin Constitution. The Petitioners have not shown beyond a reasonable doubt that the current school financing system violates either art. X, § 3, or art. I, § 1, and therefore, they have not made out a prima facie case in support of their motion for summary judgment.
¶ 89. I am authorized to state that Chief Justice SHIRLEY S. ABRAHAMSON, Justice WILLIAM A. BABLITCH, and Justice ANN WALSH BRADLEY join in the standard we have set forth in ¶ 3, ¶ 51, and ¶ 87. I am further authorized to state that Justice JON P. WILCOX, Justice DAVID T. PROSSER, and Justice DIANE S. SYKES join in our decision as to the constitutionality of the present school finance system.
*642By the Court. — The decision of the court of appeals is affirmed.
We remember Ralph Waldo Emerson's words to the Harvard graduating class of 1837:
[T]here is a portion of reading quite indispensible to a wise man [or woman]. History and exact science he [or she] must learn by laborious reading. Colleges [and public schools], in like manner, have their indispensable office — to teach elements. But they can only highly serve us when they aim not to drill, but to create; when they gather from far every ray of various genius to their hospitable halls, and by the concentrated fires, set the hearts of their youth on flame. Thought and knowledge are natures in which apparatus and *599pretension avail nothing. Gowns and pecuniary foundations, though of towns of gold, can never countervail the least sentence or syllable of wit. Forget this, and our American colleges [and public schools] will recede in their public importance, whilst they grow richer every year.
Ralph Waldo Emerson, "The American Scholar" in Ralph Waldo Emerson: Essays and Journals, 1837, at 37 (Lewis Mumford ed., 1968) (words added in brackets).
We hold that this case presents a justiciable issue. In Baker v. Carr, 369 U.S. 186, 211 (1962), the United States Supreme Court stated that a court must decide on a case-by-case inquiry whether a so-called political issue is justiciable, and "[djeciding whether a matter has in any measure been committed by the Constitution to another branch of government, or whether the action of that branch exceeds whatever authority has been committed, is itself a delicate exercise in *600constitutional interpretation...." This court on numerous occasions has interpreted the state constitution to find that assessing the constitutionality of the state school finance system is within its province. See, e.g., Kukor v. Grover, 148 Wis. 2d 469, 436 N.W.2d 568 (1989); Busé v. Smith, 74 Wis. 2d 550, 247 N.W.2d 141 (1976); State ex rel. Zilisch v. Auer, 197 Wis. 284, 221 N.W. 860 (1928).
In Kukor the court of appeals specifically certified the issue of whether the judiciary has the power to declare the system of financing unconstitutional, after the circuit court found that " '[w]hether a higher degree of uniformity is now 'practicable' is for the Legislature to decide. . . . The battle over scarce tax dollars for education is a political one. . . . The Legislature is where the framers of the constitution intended these decisions to be made.'" Kukor, 148 Wis. 2d at 483 n.8. This court clearly concluded that it does have that power by proceeding to examine the constitutionality of the school finance system. Moreover, in Busé, 74 Wis. 2d at 581, we held a portion of the school finance system unconstitutional. There we specifically stated, "to hold that the legislature is constitutionally mandated to provide an equal opportunity for education. . .is not necessarily to validate as constitutional any means chosen by the legislature to achieve that end." Id. at 567. We are satisfied that the issues presented to us in this case are appropriate for decision by this court in the exercise of our constitutional role. This is an area where all three of the co-equal branches of state government share power and authority consistent with the Wisconsin Constitution. It is indeed "a delicate exercise in constitutional interpretation."
See Wis. Stat. §§ 118.30(lg)(a) and 121.02(L) (1997-98).
The constitution refers to "common schools," "normal schools," and "district schools," instead of "public schools," which is the general terminology used today. Wis. Const, art. X, §§ 2(1), 2(2), and 3. Common schools, district schools, and nor*602mal schools were all forms of publicly funded schools. See generally, Conrad E. Patzer, Public Education in Wisconsin (1924).
The state appropriated approximately $7.72 billion in school aid for 1997-99 biennium budget. Wisconsin Legislative Fiscal Bureau, Elementary and Secondary Sch. Aids 1 (Jan. 1999).
The federal government also contributes a limited amount of aid to school districts, which is generally used for special education and remedial education. Elementary and Secondary Sch. Aids at 3. The amount of this aid is not significant for the purposes of this case, so we do not address it further in this opinion.
The legislature, as part of Wis. Stat. ch. 121 — the chapter on school finance — further includes a provision on school dis*603trict standards, which directs school boards to maintain certain licensure requirements, facility and curriculum standards, and standardized testing procedures. Wis. Stat. § 121.02 (1997-98). This statute is incorporated into the subchapter on general aid. Section 121.02(L) directs local school boards to provide regular instruction in particular courses in the elementary grades, grades 5-8, and grades 9-12.
We note that equalization aid is a component of general school aids. Elementary and Secondary Sch. Aids at 1. Other general school aids include integration aid and special adjustment aid. Id. at 11. We only discuss equalization aid in detail because many school districts do not receive either integration aid or special adjustment aid. Id. at 12. A school district receives integration aid when it transfers students to change the racial balance of the district. Id. Special adjustment aid is given to a district that is experiencing a reduction in general school aid, or when a school district is consolidating. Id. at 13. We also note that a portion of the School District of Milwaukee's equalization aid goes toward paying for the Milwaukee Parental Choice Program and charter schools. Id. at 13-14.
All subsequent references to the Wisconsin Statutes are to the 1997-98 text unless otherwise noted.
A different primary guarantee applies to various types of school districts. The primary guarantee for a K-12 school district is $2,000,000. A union high school's primary guarantee is $6,000,000, and the primary guarantee for a K-8 school is $3,000,000. This opinion focuses on the primary guarantee for K-12 school districts because most districts are in that category. Elementary and Secondary Sch. Aids at 9.
As defined in ¶ 7, "DEV" represents the district equalized value figure, and "SGV" represents the state guaranteed valuation figure.
The following is a list of the state categorical aid programs: 1) handicapped education, 2) county children with disabilities education boards (CCDEBs), 3) pupil transportation, 4) school library, 5) TEACH technology block grants, 6) TEACH training and technical assistance grants, 7) telecommunications access program, 8) technology infrastructure loans, 9) pioneering partners grants, 10) bilingual-bicultural education, 11) aid to Milwaukee Public Schools (desegregation settlement aid), 12) preschool to grade 5 grants, 13) state tuition payments; open enrollment transfer payments, 14) full-time open enrollment aid for transportation, 15) alcohol and other drug abuse (AODA) grants, 16) head start supplement, 17) nutritional programs, 18) student achievement guarantee in education (SAGE), 19) driver education, 20) children-at-risk programs, 21) peer review and mentoring, 22) CESA administration, 23) environmental education, 24) alternative schools for American Indians, 25) youth options and open enrollment transportation. Elementary and Secondary Sch. Aids at 14-25.
We refer to the Plaintiffs and Intervening Plaintiffs collectively as "Petitioners," except when referring to the procedural history of this case. Throughout this opinion, we also identify specific arguments made by either the Plaintiffs or the Intervening Plaintiffs in their briefs as "Plaintiffs-Petitioners," or "Intervening Plaintiffs-Petitioners."
Wisconsin Const, art. X, § 3 — District schools; tuition; sectarian instruction; released time — states:
The legislature shall provide by law for the establishment of district schools, which shall be as nearly uniform as practicable; and such schools shall he free and without charge for tuition to all children between the ages of 4 and 20 years; and no sectarian instruction shall be allowed therein; but the legislature by law may, for the purpose of religious instruction outside the district schools, authorize the release of students during regular school hours.
A township school system was organized and taxed through a town. Patzer, Public Education in Wisconsin at 63. Under this system, independent school districts became sub-districts of the greater township school unit. Id.
The suffrage movement has also been credited with promoting public education. Egalitarian Roots, 1981 Wis. L. Rev. at 1346 n.93.
Laws of 1848 — Of Taxes for School Purposes:
Sec. 90. It shall be the duty of the supervisors of the towns in this state to assess the taxes voted by every school district in their town, and also all other taxes provided in this chapter chargeable against such district or town upon the taxable property of the district or town respectively, and to place the same on the town assessment roll, in the column of school taxes and the same shall be collected and returned by the town treasurer in the same manner and for the same compensation as town taxes.
Sec. 91. The supervisors of each town shall assess upon the taxable property of said town a sum not less than one half of the amount received by said town from the school fund of this state, and the same shall be collected and returned in the same manner as is provided in the preceding section and shall be apportioned to the several school districts in the town in proportion to the number of children in each district between the ages of four and twenty years for the support of schools therein.
Sec. 92. The supervisors shall also assess upon the taxable property of their township two and a half mills on each dollar of the valuation thereof in each year which shall be apportioned to the several school districts in the townships for the support of schools therein, and the same shall be levied, eallected [sic] and returned in the same manner as is provided in the preceding section.
Sec. 93. Each school district at any regularly called meeting of the legal voters of said district may raise an additional tax to defray the expenses of teachers wages and contingent expenses: and said tax shall be levied collected and returned as the town taxes provided for in this act: Provided, that when a tax shall be voted in any school district meeting, the notice for such meeting shall specify the object of raising such tax.
Sec. 94. The supervisors on delivery of the warrant for the collection of taxes to the town treasurer, shall also deliver to said treasurer a written statement of the amount of school taxes, the amount raised for district purposes on taxable property of each district in the town, the amount belonging to any new district on the division of the former district and the names of all persons having judgments assessed under the provisions of this chapter, upon the taxable property of any district with the amount payable to such person on account thereof.
Sec. 95. The town treasurer of each town shall retain in his hands out of the moneys collected by him the full amount of the *617school tax collected on the assessment roll, and hold the same subject to the order of the district treasurer.
Sec. 96. Said treasurer shall from time to time apply to the county treasurer for all school moneys belonging to his town or the districts thereof, and on the receipt of the moneys to be apportioned to the districts, he shall notify the town clerk of the amount to be apportioned.
We have adopted the United States Supreme Court's treatment of plurality opinions in applying the holdings of that *621Court. Lounge Management v. Town of Trenton, 219 Wis. 2d 13, 21-22, 580 N.W.2d 156 (1998); Tomczak v. Bailey, 218 Wis. 2d 245, 284, 578 N.W.2d 166 (1998) (Crooks, J., concurring). In a plurality " 'the holding of the Court may be viewed as that position taken by those Members who concurred in the judgments on the narrowest grounds.'" Id. (quoting Gregg v. Georgia, 428 U.S. 153, 169 n.15 [] (1976) (opinion of Stewart, Powell, and Stevens, JJ.)). See also Marks v. United States, 430 U.S. 188, 193 (1977).
We also note that the plurality viewed the "character of instruction" that must be uniform as the standards set forth in Wis. Stat. § 121.02, such as "minimum standards for teacher certification, minimal number of school days, and standard school curriculum." Kukor v. Grover, 148 Wis. 2d 469, 492-93, 436 N.W.2d 568 (1989).
However, the court recognized that equal access to education is a fundamental right. Kukor, 148 Wis. 2d at 496.
The opportunity to be proficient in these core subjects must be as equal as practicable; the performance on proficiency tests is not expected to be equal. This means that poor student performance on proficiency tests in school districts is not, without much more, an indicia of the unconstitutionality of the state school finance system.
Wisconsin Stat. § 118.30 (1997-98) was the result of a coordinated effort on the part of both the executive and legislative branches of Wisconsin state government. For instance, the state superintendent is responsible for general pupil assessments given in the 4th, 8th, and 10th grade, § 118.30(l)(a), and the department must develop a high school graduation examination based on pupil academic standards if academic standards are issued by the governor. § 118.30(l)(b). In accepting and applying the standard set forth today, this court is cognizant of its role, and the respective roles of the other coequal branches of government in Wisconsin.
We also note that the state appears to fund "poor" school districts much more than it funds "wealthy" districts. The circuit court cited some excellent comparisons of the amount of state aid per pupil given to "wealthy" and "poor" school districts. For instance, according to the equalization aid estimate for 1996-97, Mequon-Thiensville (a "wealthy" district) received $724.61 in equalization aid, which was 10.6% of its $6,840.53 costs per pupil. In comparison, Antigo (a "poor" district) received $4,642.05 in equalization aid, which was 77.2% of its $6,014.20 costs per pupil. This is but one example of the more substantial state aid given to "poor" districts than to "wealthy" districts.
The state is now committed to funding two-thirds of the school districts' cost of education. 1997 Wis. Act 27.
Article I, § 1 of the Wisconsin Constitution states:
All people are bom equally free and independent, and have certain inherent rights; among these are life, liberty and the pursuit of happiness; to secure these rights, governments are instituted, deriving their just powers from the consent of the governed.
We treat the Equal Protection Clause of the Fourteenth Amendment of the United States Constitution and the Wisconsin Constitution as equivalent. Jackson v. Benson, 218 Wis. 2d 835, 900-01 n.28, 578 N.W.2d 602 (1998). As such, we refer to cases analyzing either the Fourteenth Amendment or art. I, § 1 of the Wisconsin Constitution.
We note that children do not have a fundamental right to an education under the United States Constitution. San Antonio Indep. Sch. Dist. v. Rodriguez, 411 U.S. 1, 35 (1973).
In Papasan v. Allain, 478 U.S. 265, 286 (1986), the United States Supreme Court again analyzed whether a school funding scheme violated equal protection. The Court differentiated allegations that "petitioners have been denied a minimally adequate education," and the allegations of disparity in distributing funds. Id. The court found that the petitioners had not alleged the denial of a minimally adequate education because "they [did] not allege that they receive[d] no instruction on even the educational basics." Id. Similarly in this case, the Petitioners have not alleged a violation of equal protection under art. I, § 1, since they do not allege that students lack even a basic education. Their arguments, while couched in terms of adequacy, actually allege financial disparities.