The issue before this Court is the constitutional validity of Missouri’s system for funding public schools. Plaintiffs1 allege that Missouri’s school funding formula results in a public education system that is unconstitutionally disparate and inadequate. They assert that the formula applies wrongly calculated tax assessment data, rendering incorrect “local effort” contributions and directly impacting the adequacy and equity of the education provided in Missouri’s schools. The State of Missouri defends the school funding formula, arguing that it is constitutional and that it incorporates appropriate tax assessment data.2
After extensive discovery and a trial lasting more than a month,3 the trial court found against Plaintiffs, denying some claims on their merits and dismissing others. This appeal follows.
Exclusive jurisdiction of Plaintiffs’ appeal is in this Court pursuant to Missouri *482Constitution article V, section 3, as the case presents a challenge to the constitutional validity of a Missouri statute.
This Court agrees with the trial court that Plaintiffs have not shown they are entitled to relief and affirms its judgment.4
I. Background
Plaintiffs originally brought suit to challenge Missouri’s school funding formula as it existed in 2004, referred to generally as Senate Bill No. 380 (1993) (SB380). They alleged that Missouri’s school funding formula was unconstitutional because it resulted in inadequate and inequitable funding to Missouri’s public schools. They maintained that the inadequacies of that school funding formula undermined article IX, section 1(a), of the Missouri Constitution, which directs that the State provide all persons under 21 years of age a free public education to promote “[a] general diffusion of knowledge and intelligence.”5
As Plaintiffs’ case proceeded, the legislature amended the school funding formula in 2005. As such, this case has evolved into a challenge of Missouri’s current school funding formula, adopted in Senate Bill No. 287 (2005) (SB287).6
SB287’s revisions to the school funding formula were made after a joint legislative committee, the Joint Interim Committee on Education, investigated concerns that Missouri’s school funding scheme was inadequate and inequitable. This investigation led to the passage of SB287 during the 2005 legislative session. SB287’s funding formula is codified in chapter 163, RSMo Supp.2008.7
In simplified form, this formula provides state aid to Missouri’s public schools under the following calculation:
[weighted average daily attendance8]
x [state adequacy target9]
x [dollar value modifier10]
= subtotal of dollars needed
*483- [local effort11]
= state funding
The revised formula attempted to remedy inequities resulting from school funding that is financed in part by state funds and in part by local funds. It reflected a view that schools with greater “local effort” contributions require less state financial assistance to meet the costs of providing a free public education.
SB287’s formula was designed to be phased in over seven years, with the old formula under SB380 still accounting for a large portion of the calculated state aid at the outset.12 Both the SB380 and SB287 formulas applied assessed valuation calculations about which the Plaintiffs complain in this case. Plaintiffs’ assessment complaints and constitutional arguments are similar in that they both allege that Missouri’s school funding formula fails to fund its public schools adequately.
At trial, Plaintiffs presented evidence of alleged inadequacy through “focus district” plaintiff schools, whose funding under SB287’s formula failed to meet the required “state adequacy target.” Plaintiffs stressed that the alleged inadequacy of school funding in Missouri most impacts Missouri’s high-risk children, such as those living in poverty and those with special needs. They also highlighted the spending disparities among Missouri’s school districts, with per-pupil spending ranging from $4,704.11 in the Diamond R-IV School District to $15,251.28 in the Gorin R-III School District. And they noted the differences among the tax bases in Missouri’s school districts, with assessed valuation per eligible pupil in the 2004-2005 school year ranging from $19,605 in the Cooter R-IV School District to $416,679 in the Clayton School District.
Plaintiffs argued the assessed valuation calculations incorporated into SB287’s funding formula were inaccurate. They contended that the legislature acted irrationally in relying on 2004 tax assessment data that they assert were calculated unlawfully by the State Tax Commission through a failure of its oversight and equalization responsibilities. They argued that Missouri’s assessed valuations were not on pace with market values and suggested that the legislature compounded this mistake by “freezing” the 2004 assessment data into the funding formula. Their evidence included a study critical of Missouri’s school funding formula that was conducted at the Public Policy Research Center (PPRC) at the University of Missouri-St. Louis. This study, “Disparity of Assessment Results: Why Missouri’s School Funding Formula Doesn’t Add Up” (hereinafter PPRC Study), was reported in October 2006. The PPRC Study concluded that SB287’s funding formula was based wrongly on assessment calculations that varied widely throughout the state and that, in many cases, were unacceptably low because they did not reflect market values.
An education finance expert testified on Plaintiffs’ behalf that Missouri’s school finance system was “one of the most disparate systems in existence in the United States” because SB287’s funding formula placed a greater financial burden on local school districts by increasing their responsibility for funding public schools. Plaintiffs acknowledged that SB287’s formula revisions would contribute more than $2 million in additional funds for Missouri’s schools but noted that the increased monies were far below the additional $904.8 million in funds that Missouri’s State *484Board of Education had determined were necessary to fund Missouri’s public schools adequately.
Defendants countered Plaintiffs’ evidence by stressing that SB287 would provide an additional $800 million for Missouri’s public education system when fully phased in. They stressed that the long-term goal of SB287 was to move Missouri’s funding formula to a need-based, rather than a tax-based, system to provide increased state aid to poorer school districts. They also asserted that the funding produced under the SB287 formula is constitutional because it complies with the funding mandate outlined in article IX, section 3(b), of the Missouri Constitution, which provides that the State “set apart [no] less than [25] percent of the state revenue, exclusive of interest and sinking fund, to be applied annually to the support of the free public schools.”13
The trial court agreed with Defendants that the State is not required to provide its public schools funding beyond 25 percent of the State’s revenue, as directed by article IX, section 3(b). It noted that the legislature may provide additional monies, but it determined that no Missouri constitutional provision requires allocation of increased funding. The trial court also found that Plaintiffs had not shown that SB287 violated the Missouri Constitution’s Hancock Amendment or that it provided the remedy sought. The trial court dismissed the assessment calculation issues on standing and jurisdictional grounds, and it rejected Plaintiffs’ claims that the legislature wrongly relied on the State Tax Commission’s 2004 assessment data.
Plaintiffs appeal the trial court’s judgment, raising four categories of challenges to Missouri’s school funding formula: (1) the formula “inadequately” funds schools in violation of article IX of the Missouri Constitution; (2) the formula violates equal protection; (3) the formula violates Missouri’s Hancock Amendment; and (4) the legislature violated article X of the Missouri Constitution and certain statutes by incorporating inaccurate assessment figures into the formula. These issues are addressed separately below.
II. Procedural Issues
Before addressing Plaintiffs’ challenges to the school funding formula, this Court addresses two threshold issues: (1) Plaintiffs’ standing; and (2) the joining of defendant-intervenors.
A. Standing
This Court must address issues of standing before exploring Plaintiffs’ constitutional challenges. See, e.g., Conseco Fin. Servicing Corp. v. Mo. Dep’t of Revenue, 195 S.W.3d 410, 413 n. 3 (Mo. banc 2006). Standing is reviewed de novo. Mo. State Med. Ass’n v. State, 256 S.W.3d 85, 87 (Mo. banc 2008). Standing requires that a party seeking relief has some legally protectable interest in the litigation so as to be affected directly and adversely by its outcome, “even if that interest is attenuated, slight or remote.” Id.
Defendants challenge Plaintiffs’ standing on several grounds, which are detailed below.
1. School District Organizations
Defendants contend that the plaintiff school districts and their representative not-for-profit advocacy organizations lack standing to litigate constitutional claims concerning individual rights. For *485an organization to have standing, its members must have standing, the interests it seeks to protect must be germane to the organization’s purpose, and the participation of individual members must not be required. Mo. Health Care Ass’n v. Attorney Gen. of Mo., 953 S.W.2d 617, 620 (Mo. banc 1997).
This Court has stated that “the capacity of a school district to sue and its authority to prosecute actions required to protect and preserve school funds and property is necessarily implied from the district’s duty to maintain schools and conduct instruction within its boundaries.” State ex rel. Sch. Dist. of Independence v. Jones, 653 S.W.2d 178, 185 (Mo. banc 1983) (finding that school districts were not barred from bringing a declaratory judgment challenge to the State Tax Commission’s future calculations of school funding monies).
Arguing that their duties are impaired, Plaintiffs assert that article IX, section 1(a), of the Missouri Constitution, which guarantees free public schools, also contains a requirement for “adequate” funding for those schools. Because they argue that, under their interpretation, school districts would be entitled to more funds, the plaintiff school districts and their representative organizations have standing to challenge the school funding formula under article IX, section 1(a). See Comm. for Educ. Equal. v. State, 878 S.W.2d 446, 458 (Mo. banc 1994) (Robertson, J. concurring) (suggesting that school district standing was proper under article IX, section 1(a)); Gerken v. Sherman, 276 S.W.3d 844, 853 (Mo.App.2009) (stating that public schools have a legal interest directly jeopardized when the state failed to place certain funds into the public school fund).
Similarly, school districts and their representative organizations have standing for their assessment challenges raised under article X, concerning taxation, in that they allege the legislature wrongly relied on inaccurate tax assessment data. They contend this impacts their duty to provide a free public education under article IX, section 1(a) in that an injury results from use of inaccurate assessment data in “local effort” calculations.
School districts and their representative organizations lack standing to assert that the alleged inadequacy of school funding violates their equal protection rights or the Hancock Amendment. Political subdivisions established by the State are not “persons” within the protection of the due process and equal protection clauses. City of Chesterfield v. Dir. of Revenue, 811 S.W.2d 375, 377 (Mo. banc 1991). Also, the Hancock Amendment by its terms does not grant standing to school districts or their representative organizations. Mo. Const, art. 10, sec. 23 (granting taxpayers standing to sue under the Hancock Amendment).
2. Taxpayers
Defendants also argue that individual taxpayer plaintiffs lack standing to bring challenges to other taxpayers’ property tax assessments, as they are not injured personally by others’ assessment calculations. See W.R. Grace & Co. v. Hughlett, 729 S.W.2d 203, 206-07 (Mo. banc 1987) (finding that a plaintiff did not have standing to challenge excused tax obligations of others). “The primary basis for taxpayer suits arises from the need to ensure that government officials conform to the law.” E. Mo. Laborers Dist. Council v. St. Louis County, 781 S.W.2d 43, 46 (Mo. banc 1989).
Plaintiff taxpayers have standing to raise their assessment challenges to the extent that they allege that the State is spending tax revenue improperly under *486articles IX and X of the Missouri Constitution, which concern expenditures related to free public schools and tax revenue. See Ste. Genevieve Sch. Dist. R-II v. Bd. of Aldermen, 66 S.W.3d 6, 11 (Mo. banc 2002) (finding that a taxpayer had standing to seek a declaratory judgment that the city was acting beyond its authority where a redevelopment project would cost the school district and the city future tax revenue).
But, as is the case for school districts and their representative organizations, plaintiff taxpayers do not have standing to bring equal protection claims on behalf of public school students generally. See Comm. for Educ. Equal., 878 S.W.2d at 450 (claims of equal protection rights generally may not be raised by third parties).
3. Students
Defendants additionally suggest that the student plaintiffs in this case lack standing, arguing their claims are rendered moot because they are not currently enrolled in school. But plaintiff students’ standing is not moot, as multiple plaintiff students remain in the public school system. Further, plaintiff students who are no longer in Missouri’s public schools have claims that are not moot because they present claims capable of repetition that otherwise may evade review. See In re 1983 Budget for Circuit Court of St. Louis County, 665 S.W.2d 943, 943 n. 1 (Mo. banc 1984) (noting that claims capable of repetition that otherwise may evade review need not be considered moot).
In sum, having determined that at least one plaintiff has standing as to each claim, the merits of each of Plaintiffs’ challenges to SB287 are addressed below. See Massachusetts v. EPA, 549 U.S. 497, 518, 127 S.Ct. 1438, 167 L.Ed.2d 248 (2007) (stating the rule that only one of the plaintiffs needs standing to permit consideration of a claim).
B. Defendant-Intervenors
Plaintiffs argue that the trial court erred in granting permissive intervention to three taxpayers seeking to join the State’s defense of SB287’s school funding formula.14 Defendant-Intervenors sought to join this case shortly before the trial,15 and their motion to intervene was opposed by Plaintiffs and the State.16 Plaintiffs asserted that permissive intervention was improper because Defendant-Intervenors asserted no interest apart from that of general taxpayers.17 The State highlighted that Defendant-Interve-nors asserted no property or transactional interests in the constitutional validity of the school funding formula, and it asserted that it adequately could guard the public’s *487interests in defending SB287.18 The trial court, however, elected to allow Defendant-Intervenors to join as defendants under Rule 52.12(b), permissive intervention. In permitting Defendant-Intervenors to join, the court noted the peculiarity of this ease and its statewide significance, but it specifically stated that the State’s interests already were adequately represented.
This Court reviews permissive intervention for abuse of discretion. State ex rel. Nixon v. Am. Tobacco Co., 34 S.W.3d 122, 131 (Mo. banc 2000). Permissive intervention is provided for by Rule 52.12(b) in three circumstances: (1) when allowed by statute; (2) when an applicant’s claim or defense and the main action have a question of law or fact in common; or (3) when the State is seeking intervention in a case raising constitutional or statutory challenges. None of these circumstances apply to Defendant-Intervenors. The provision allowing intervention when an applicant’s claim or defense and the main action have a question of law or fact in common is inapplicable to Defendant-Intervenors because they merely reasserted the State’s defenses. Defendant-Intervenors asserted no claim, defense, or interest unique to themselves. They have not shown that the State could not or did not defend its interests adequately. As such, Rule 52.12(b) provided no mechanism by which Defendant-Intervenors could join the State’s defense of the constitutional validity of SB287.
Further, Missouri’s taxpayer standing doctrine does not apply to Defendant-Intervenors, as that doctrine concerns taxpayer plaintiffs seeking to restrain the State from improperly spending tax revenue. See Ste. Genevieve Sch. Dist., 66 S.W.3d at 11. Here, Defendant-Intervenors, as defendants, neither challenged the State’s expenditures nor sought to restrain the State in any manner. Instead, they sought to defend the status quo funding formula, the very position the State took below. Applying taxpayer standing to Defendant-Intervenors would open the floodgates to allow all Missouri taxpayers to seek intervention in the State’s defense of constitutional and statutory challenges. No public policy is served by allowing intervention premised on a taxpayer’s mere interest in the subject matter of a suit. Defendant-Intervenors here could have sought leave to express their views in an amicus brief, rather than through intervention.
The trial court erred in permitting Defendant-Intervenors to join this case. But this intervention error does not merit reversal unless Plaintiffs were harmed. Cf. St. Louis County v. Vill. of Peerless Park, 726 S.W.2d 405, 410 (Mo.App.1987) (finding no prejudice from an intervention by defendants where the plaintiff was found to lack standing and a final judgment already had been entered against the plaintiff, calling the decision to allow intervention “no longer alive”).
Plaintiffs have not demonstrated specific harm or litigation costs caused by Defendant-Intervenors’ presence in this case. Further, Defendant-Intervenors aver that they have abandoned their previous re*488quests to collect costs from Plaintiffs. Under these circumstances, no material harm to Plaintiffs is evident. Accordingly, the trial court’s error in permitting this intervention does not require reversal.
III. School funding formula does not violate article IX
Missouri Constitution article IX, section 3(b) provides:
In event the public school fund provided and set apart by law for the support of free public schools, [sic] shall be insufficient to sustain free schools at least eight months in every year in each school district of the state, the general assembly may provide for such deficiency; but in no case shall there be set apart less than [25] percent of the state revenue, exclusive of interest and sinking fund, to be applied annually to the support of the free public schools.
Plaintiffs do not argue that the State has failed in its obligations under this section. Instead, Plaintiffs contend that SB287’s failure to provide school funding beyond that granted by section 3(b) contravenes Missouri Constitution article IX, section 1(a), because the SB287 school funding formula fails to “adequately” provide the “general diffusion of knowledge and intelligence” mandated by section 1(a).
The constitutional validity of SB287 and the trial court’s interpretation of the Missouri Constitution are questions of law given de novo review. City of Arnold v. Tourkakis, 249 S.W.3d 202, 204 (Mo. banc 2008). Legislative acts are entitled to deference, and this Court must give these acts any reasonable construction to avoid nullifying them. Bd. of Educ. v. City of St. Louis, 879 S.W.2d 530, 533 (Mo. banc 1994). In the absence of a constitutional prohibition, the legislature has the power to enact legislation on any subject. Id. Constitutional provisions are read in harmony with all related provisions. Neske v. City of St. Louis, 218 S.W.3d 417, 421 (Mo. banc 2007).
Initially, this Court must determine the significance of section l(a)’s language as read in harmony with section 3(b). See id. Article IX, section 1(a), states:
A general diffusion of knowledge and intelligence being essential to the preservation of the rights and liberties of the people, the general assembly shall establish and maintain free public schools for the gratuitous instruction of all persons in this state within ages not in excess of [21] years as prescribed by law.
Notably, the introductory clause in section 1(a) concerning the “diffusion of knowledge” outlines the purpose and subject of Missouri’s public education system. But, it provides no specific directive or standard for how the State must accomplish a “diffusion of knowledge.” Plaintiffs are attempting to read a separate funding requirement into section 1(a) that would require the legislature to provide “adequate” education funding in excess of the 25-percent requirement contained in section 3(b). Such language does not exist.
The lack of specificity in section l(a)’s introductory clause can be contrasted with the remainder of section 1(a) that specifically requires free public schools and sets the maximum student age at 21 years. This Court interpreted the directive in the body of section 1(a) in Concerned Parents v. Caruthersville School District 18, 548 S.W.2d 554, 559 (Mo. banc 1977). Concerned Parents notes that article IX, section l(a)’s language, as a whole, including the introductory portion of the section, requires the State to provide free public schools that charge no admission or course fees. Id. at 562. The introductory clause alone, however, has never been given di*489rect effect, as it is purely aspirational in nature.
Reading a free-standing obligation to provide certain school funding into the introductory language of section 1(a) would be contrary to the specific flexibility afforded the legislature in article IX, section 3(b). See Comm. for Educ. Equal., 878 S.W.2d at 458 (Robertson, J. concurring) (commenting that section 1(a) does not create a substantive funding obligation in the legislature independent of section 3(b)). Section 3(b) does not limit the legislature’s power in section 1(a) to establish and maintain free public schools. See State ex rel. Sharp v. Miller, 65 Mo. 50 (Mo.1877) (addressing a former version of section 3(b)’s 25 percent requirement and noting that the legislature may appropriate more than provided for in that section). Rather, section 3(b) provides the legislature a flexible framework for funding Missouri’s public schools. It indicates the minimum level of funding that the legislature “shall” set aside — at least 25 percent of the state revenue. But it also outlines that the legislature “may” provide additional funding to account for deficiencies. It is the language of section 3(b), not the aspirational introductory language of section 1(a), that provides the constitutional parameters for funding Missouri’s public schools.
Plaintiffs’ claims that SB287’s funding formula is unconstitutional because it fails to provide funding required by article IX, section 1(a) are without merit. Where the legislature has provided the 25 percent of state revenue required by section 3(b), it has not failed in its duty under section 1(a) to provide free public education. Inasmuch as section 1(a) presents a community aspiration, it is the legislature’s prerogative to consider its relevance and act accordingly.19 The judiciary cannot invade the legislative branch’s province to fund schools beyond the requirements of section 3(b). See, e.g., State ex rel. Crow v. Bland, 144 Mo. 534, 46 S.W. 440, 446 (1898) (“[U]nder the division of powers in our form of government, we have no right to trench upon the prerogatives of the other co-ordinate branches of our government.”). The aspiration for a “general diffusion of knowledge and intelligence” concerns policy decisions, and these political choices are left to the discretion of the other branches of government.
IY. School funding formula does not violate equal protection
Plaintiffs also contend that SB287’s school funding formula violates Missouri Constitution article I, section 2, Missouri’s equal protection provision, arguing the formula results in “inadequate” funding to certain school districts and yields differences in per-pupil expenditures among school districts.
Missouri Constitution article I, section 2, guarantees equal rights and opportunities under the law. Doe v. Phillips, 194 S.W.3d 833, 845 (Mo. banc 2006). Like the 14th Amendment of the United States Constitution, article 1, section 2 of Missouri’s Constitution provides that a law may treat different groups differently, but it cannot treat similarly situated persons differently without adequate justification. Id. “What constitutes adequate justifica*490tion for treating groups differently depends on the nature of the distinction made.” Id. Where a law impacts a “fundamental right,” this Court applies strict scrutiny, determining whether the law is necessary to accomplish a compelling state interest. Id. But, where this Court finds that a fundamental right is not impacted, this Court gives an equal protection claim rational-basis review, assessing whether the challenged law rationally is related to some legitimate end. Id.
Plaintiffs contend that school funding “adequacy” and per-pupil expenditure equity are fundamental rights in Missouri based on article IX, section l(a)’s provision for “[a] general diffusion of knowledge and intelligence.” Fundamental rights are those “deeply rooted in the nation’s history and tradition and implicit in the concept of ordered liberty, such that neither liberty nor justice would exist if they were sacrificed.” State ex rel. Nixon v. Powell, 167 S.W.3d 702, 705 (Mo. banc 2005). Education is not a fundamental right under the United States Constitution’s equal protection provision. See San Antonio Indep. Sch. Dist. v. Rodriguez, 411 U.S. 1, 93 S.Ct. 1278, 36 L.Ed.2d 16 (1973). And, although Missouri’s Constitution may contain additional protections, Missouri courts have followed the general federal approach to defining fundamental rights. See In re Marriage of Woodson, 92 S.W.3d 780, 783 (Mo. banc 2003) (quoting Washington v. Glucksberg, 521 U.S. 702, 720, 117 S.Ct. 2258, 138 L.Ed.2d 772 (1997)).
To resolve Plaintiffs’ contention that equitable education spending should be regarded as a fundamental right under the Missouri Constitution, this Court examines Missouri Constitution article IX, which contains specific provisions for education. See Phillips, 194 S.W.3d at 843 (stating that “if a particular constitutional amendment provides specific protection for the right asserted ... the alleged violation will be analyzed under that amendment”). Notably, no expressed right to equitable education funding exists in article IX, section l(a)’s provision for free public schools. And, as stated above, the introductory clause of article IX, section 1(a) does not describe a free-standing right to “adequate” funding.
Further, article IX does not contain a mandate for equitable per-pupil expenditures among districts. Missouri’s 1865 Constitution contained language regarding equitable educational funding, but that language was removed in the 1875 Constitution and never has been restored.20 Missouri’s current constitution does not contain such language and instead builds in certain variances. For example, the proceeds of penalties, forfeitures, and fines are placed in the school funds of the individual counties. Mo. Const, art. IX, sec. 7. And article X, section 11(c) allows for varying tax levies in municipalities, counties, and school districts by local vote. The inevitable result of including these and other provisions in the Missouri Constitution is variance in per-pupil spending across districts. There is no constitutional basis for implying an equal per-pupil spending requirement.
Because Missouri’s education article contains neither a free-standing “adequacy” requirement nor an equalizing mandate, Plaintiffs have failed to show that SB287 impacts a fundamental right. Accordingly, strict scrutiny does not apply. Instead, under rational basis review, this *491Court analyzes whether SB287’s school funding formula rationally relates to a legitimate end. Phillips, 194 S.W.3d at 845. Rational basis review does not question “the wisdom, social desirability or economic policy underlying a statute,” and a law is upheld if it is justified by any set of facts. Mo. Prosecuting Attorneys & Circuit Attorneys Ret. Sys. v. Pemiscot County, 256 S.W.3d 98, 102 (Mo. banc 2008) (internal citation omitted).
SB287’s funding formula satisfies this highly deferential standard because funding free public schools in Missouri is clearly a legitimate end. See Mo. Const., art. IX, sec. 1(a). And funding schools in a way that envisions a combination of state funds and local funds, with the state funds going disproportionately to those schools with fewer local funds, cannot be said to be irrational. As discussed above, no provision of the Missouri Constitution forbids funding in this manner, and no mandate requires that per-pupil expenditures be equal. See Thompson v. Comm. on Legislative Research, 932 S.W.2d 392, 394 (Mo. banc 1996) (stating that the legislature has plenary power and may act unless denied power to do so in the constitution). As such, Plaintiffs’ arguments that SB287 violates Missouri’s equal protection clause are without merit.
V. School funding formula does not violate the Hancock Amendment
Plaintiffs further allege that SB287 is unconstitutional because it violates Missouri’s Hancock Amendment, Missouri Constitution article X, sections 16 through 24. In particular, Plaintiffs assert that the State violated section 16 of the Hancock Amendment by requiring new programs without funding them and violated section 21 by reducing the state-financed portion of certain education programs.
Section 23 of the Hancock Amendment provides specific types of relief to taxpayers:
Taxpayers may bring actions for interpretations of limitations[: ] Notwithstanding other provisions of this constitution or other law, any taxpayer of the state, county or other political subdivision shall have standing to bring suit ... to enforce the provisions of sections 16 through 22, inclusive, of this article and, if the suit is sustained, shall receive from the applicable unit of government his costs, including reasonable attorneys’ fees incurred in maintaining such suit.
Mo. Const, art. X, sec. 23.
This Court has noted that this section’s heading, “Taxpayers may bring actions for interpretations of limitations,” merely authorizes declaratory relief. See Taylor v. State, 247 S.W.3d 546, 548 (Mo. banc 2008). And “[t]he limited nature of the declaratory, or interpretive, remedy does not authorize a court to enter a judgment for damages or injunctive relief.” Id. Indeed, as the general purpose of the Hancock Amendment is to limit governmental expenditures, this Court has found that section 23 cannot be read as a waiver of sovereign immunity for money judgments against the State. See Fort Zumwalt Sch. Dist. v. State, 896 S.W.2d 918, 923 (Mo. banc 1995) (stating that section 23 does not constitute consent to a suit for a money judgment to enforce section 21). Rather, a proper remedy is “a declaratory judgment relieving a local government of the duty to perform an inadequately funded required service or activity.” Id.
In this case, however, Plaintiffs expressly do not seek to have plaintiff school districts released from any alleged unfunded obligations. Instead, they in essence request a declaratory judgment that *492results in increased funding. This remedy is unavailable under the Hancock Amendment.
For support of its requested remedy, Plaintiffs point to Taylor’s statement that “[i]nherent in the courts’ power to enter a declaratory judgment ... is the power of the court to enforce the judgment through other forms of relief where a party acts contrary to a court’s declaratory judgment.” 247 S.W.3d at 549. This inherent power, however, provides no remedy under section 23. See, e.g., City of Jefferson v. Mo. Dep’t of Natural Res., 916 S.W.2d 794, 796 (Mo. banc 1996) (applying this rule to find the remedy for a Hancock violation was noncompliance with the mandate until the state actually reimbursed the city for its increased costs). Because Plaintiffs expressly disaffirm that they seek to be released from any mandate, their Hancock Amendment challenge necessarily fails.21
VI. School funding formula does not violate article X or other statutes
Plaintiffs argue that SB287’s funding formula is unconstitutional under Missouri Constitution article X, sections 3, 4, and 14, and that it violates several Missouri statutes.22 They contend that the State Tax Commission did not follow the mandates found in these constitutional and statutory provisions in reporting its 2004 assessments for school funding purposes. More particularly, they allege that the legislature acted unlawfully when incorporating and freezing the Commission’s 2004 property tax assessments into SB287’s school funding formula.23 They contend that use of these allegedly flawed 2004 assessments render incorrect the “local ef*493fort” calculations of SB287’s funding formula, leading to the improper distribution of state funds. See section 163.011(1).
To prevail, Plaintiffs must show that SB287’s funding formula conflicts with the constitutional provisions they have raised. See Cannon v. Cannon, 280 S.W.3d 79, 83 (Mo. banc 2009) (noting that a statute will be held invalid if it conflicts with the constitution). As relevant to their argument, the constitutional and statutory provisions cited by Plaintiffs speak on their face to what the Commission must do and outline certain procedures for these mandates. For example, article X, section 3 requires that “taxes shall be uniform upon the same class or subclass of subjects.” But Plaintiffs do not allege that the legislature has promulgated a statute that itself levies non-uniform taxes; rather, they allege that the legislature wrongly relied on the Commission’s 2004 property assessment figures. Similarly, article X, section 14 requires that the Commission equalize assessments. But this provision does not indicate what the legislature may or must do regarding the Commission’s assessments.
The separate opinion criticizes the equality of Missouri’s tax assessment scheme and the assessment data the Commission calculated, and it further highlights that unconstitutionally disparate taxation is disallowed pursuant to this Court’s opinion in State ex rel. School District of City of Independence v. Jones, 653 S.W.2d 178 (Mo. banc 1983). The Commission was a party to Jones, 653 S.W.2d at 180-81. The Commission, however, was never joined as a necessary party to this case, which prevents evaluation of its actions. See Rule 52.04 (“Joinder of Persons Needed for Just Adjudication”). Plaintiffs implicitly recognized this when they expressly abandoned any direct attack on the propriety of the Commission’s property tax assessment procedures and equalization methods under Missouri law.
For these reasons, although the separate opinion raises complex and important issues concerning Missouri’s assessment scheme and its relationship to educational financing, the question of equalizing assessments is for another day. This Court’s role is limited to deciding the issues before it and not making advisory opinions. See City of Springfield v. Sprint Spectrum, L.P., 203 S.W.3d 177, 188 (Mo. banc 2006) (recognizing that this Court has no authority to render an advisory opinion); Schottel v. State, 159 S.W.3d 836, 841 (Mo. banc 2005) (“[t]his Court cannot offer advisory opinions on issues that may arise in the future”).
Plaintiffs additionally cannot show that the constitutional provisions they invoke restrict the legislature’s discretion in shaping the school funding formula.24 And, in the absence of a constitutional bar, it is clear that the legislature has plenary power to act in crafting the school funding formula. See Thompson, 932 S.W.2d at 394.
Lacking an actual conflict with the Missouri Constitution, Plaintiffs are left to argue that the legislature acted irrationally or arbitrarily when relying on the Commission’s 2004 assessment data. They criticize the quality of the Commission’s data by presenting the PPRC Report demon*494strating the Commission’s assessment flaws and pointing to aspects of the Commission’s assessment practices that did not conform to statutory and constitutional provisions.25 There is, however, no record basis to hold, as the separate opinion suggests, that the legislature’s reliance on the Commission’s 2004 assessment data was irrational.
Plaintiffs reliance on the PPRC Report is misplaced, as the PPRC Report was created after the passage of SB287, and the legislature did not have this information available when debating revisions to the school funding formula in 2005. Moreover, property assessment is not an exact science, and, even were the Commission’s 2004 data imperfect, use of that data was not an irrational act by the legislature. The joint committee studying Missouri’s school funding formula in 2004 found that the school funding system suffered from inequities and deficiencies. Its report called for a new formula. The legislature, responding to these and other findings, constructed a new school funding system during the 2005 legislative session. This system incorporated the most current information then available from the Commission, the 2004 data. The argument that a perhaps better or more proper assessment practice was available to the Commission is not determinative under the rational basis review afforded SB287. See Pemiscot County, 256 S.W.3d at 102-03. Further, Plaintiffs’ evidence did not go unchallenged. Defendants presented testimony that the Commission’s assessment data did not necessarily provide an inferior indicator of property value as compared to sales data, and in some cases Defendants’ approach may hold certain advantages as it opens up a greater pool of data. The legislature’s reliance on the Commission’s data was permissible because it was a rational attempt toward the legitimate end of funding Missouri’s free public schools.
Although judicial review of legislative enactments is fundamental to our system of checks and balances, hindsight evaluation of the quality of data on which the legislature relied is not appropriate in this case. Assessing the wisdom of the legislature’s reliance on the Commission’s data would invade the legislature’s deliberative process and violate the separation of powers between the judicial and legislative branches of government. See Pemiscot County, 256 S.W.3d 98, 102-03 (stating that rational basis review merely asks if any set of facts can be reasonably conceived to justify the law).
Similarly, this Court finds no basis to declare the decision to phase in SB287 over seven years irrational, nor is the act of freezing in the 2004 data irrational. By phasing in the formula, the legislature may have wished to promote continuity between the old and new funding systems. Further, freezing the assessment data used is consistent with the historical practice of revisiting the school funding formula approximately every 10 years. See Final Report of the Joint Interim Committee on Education (Feb. 15, 2004). Likewise, *495the legislature could choose to rewrite the funding formula at any time. Inasmuch as Plaintiffs express concern over possible funding deprivations after 2013, that concern is merely speculative.
SB287 does not conflict impermissibly with the provisions highlighted by Plaintiffs, and it survives rational basis review. As such, Plaintiffs’ assessment arguments are unpersuasive.
VII. Conclusion
For the foregoing reasons, this Court finds no error in the trial court’s findings upholding the constitutional validity of SB287’s school funding formula. The trial court’s judgment is affirmed.
PRICE, C.J., BRECKENRIDGE, FISCHER and LAURA DENVER STITH, JJ., and PARRISH, Sp.J., concur. WOLFF, J., concurs in part and dissents in part in separate opinion filed. TEITELMAN, J., not participating..All plaintiffs in this case, including plaintiff-intervenors, are referred to collectively in this opinion as Plaintiffs. Plaintiffs include two not-for-profit education advocacy groups, the Committee for Educational Equality (CEE) and the Coalition to Fund Excellent Schools (CFES), which each represent member school districts. CEE, together with certain school districts, students, parents, and taxpayers, raised constitutional challenges to Missouri's school funding formula. CFES, together with the Board of Education of the City of St. Louis, certain school districts, students, parents, and taxpayers, intervened in CEE's constitutional claims and raised a separate challenge to the tax assessment calculations underlying the funding formula. Plaintiffs include 271 of Missouri's 524 school districts.
. The defendants in this case include the State of Missouri, the State Treasurer, the State Board of Education, the Department of Elementary and Secondary Education, the Missouri Commissioner of Education, the Commissioner of Administration, and Missouri's Attorney General. These defendants are referred to collectively in this opinion as Defendants.
. This case includes a 36-volume legal file (6,418 pages), a 34-volume trial transcript (8,552 pages), and various transcripts of related proceedings.
. The trial court found that CFES plaintiffs did not have standing to challenge the tax assessment calculations incorporated into the school funding formula because they could not challenge the assessments of others and had failed to join the State Tax Commission as a necessary party. CFES plaintiffs do not pursue this assessment issue in this appeal. CFES plaintiffs raised a second assessment-related claim, arguing that the legislature arbitrarily relied on 2004 tax assessments from the State Tax Commission. The trial court made no findings as to CFES plaintiffs’ standing as to this second claim, which is addressed in this opinion.
. Plaintiffs have provided a thorough history of Missouri's constitutional provisions for public education. Missouri's role in providing its citizens a public education was outlined in its territorial charter in 1812, which stated: "[Kjnowledge, being necessary to good government and the happiness of mankind, schools and the means of public education shall be encouraged and provided for[.]” Territorial Laws of Missouri, vol. I, ch. IV, sec. 14 (page 13) (approved June 4, 1812).
. SB287 as truly agreed to and finally passed by the legislature and signed by the governor incorporated a number of modifications and amendments from the bill as originally filed, but these modifications are not relevant here. By its terms, SB287 became effective July 1, 2006.
. All statutory references in this opinion are to RSMo Supp. 2008, unless otherwise indicated.
. This figure accounts for the average number of students and also accounts for student needs.
. This number is a per-pupil spending target that is defined and calculated according to section 163.011(18). Its calculation includes certain “current operation expenditures” defined in section 163.011(3). For 2007 and 2008, the state adequacy target was set at $6,117.
. This number adjusts for variations in costs across the state.
. "Local effort” is calculated according to section 163.011(10).
. Section 163.031.4 provides phase-in calculations applying both the SB380 and SB287 formulas through the 2011-2012 school year.
. Plaintiffs did not challenge that the State failed to meet the 25-percent requirement in article IX, section 3(b).
. The three taxpayers are W. Bevis Schock, Rex Sinquefield, and Menlo Smith (collectively Defendant-Intervenors).
. This case was commenced in 2004, but Defendant-Intervenors did not seek to join the case until October 2006, three months prior to its January 2007 trial setting.
. The State defendants do not join in Defendant-Intervenors’ arguments to this Court regarding permissive intervention.
.Defendant-Intervenors assert that Plaintiffs are too late in contesting the trial court's order permitting intervention. The order permitting intervention, however, was not a final order from which Plaintiffs could have appealed, and Plaintiffs properly raise this issue as part of this appeal. See Aversman v. Danner, 577 S.W.2d 910, 911 (Mo.App.1979) (finding interlocutory a decision to permit intervention and noting that "[(Intervention permitted merely moves the cause forward on the merits with full right reserved at a future date for review on appeal”).
. The doctrine of parens patriae creates a rebuttable presumption that the government adequately represents the public’s interests in cases concerning matters of sovereign interest. See Curry v. Regents of Univ. of Minn., 167 F.3d 420, 423 (8th Cir.1999) (addressing both permissive and as-of-right intervention); see also State ex rel. Cooper v. Wash. County Comm’n, 848 S.W.2d 620, 622 (Mo.App.1993) (finding in an intervention as-of-right matter that a private person is not entitled to intervene "[w]hen a public officer is engaged in litigation to protect public rights, and the officer's pleadings and procedure maintain the public interest”).
. Plaintiffs presented evidence that many districts could not meet their school facility and infrastructure needs sufficiently. Additionally, they pointed to funding needs of early childhood education programs. And they raised the issue of school transportation costs, which are funded separately by the State but which are subject to unaccounted-for funding shortfalls. But, because section 1(a) provides no free-standing funding obligation, these and related arguments are without merit.
. See Mo. Const. 1865, art. IX, sec. 9 ("The general assembly shall ... make such distribution as will equalize the amount appropriated for common schools throughout the State.").
. In addition to finding that Plaintiffs' requested remedy was unavailable under the Hancock Amendment, the trial court also found that Plaintiffs' substantive arguments regarding preexisting and new mandates were without merit. Regarding the substantive arguments, the trial court found that Plaintiffs' evidence was insufficient because it failed to provide the required budgetary evidence of changes in state reimbursement rates, evidence of costs in 1980 to 1981, and evidence of the related funding ratios. See Fort Zumwalt, 896 S.W.2d at 922. Plaintiffs also pointed to new performance and accountability standards in SB380, but the trial court found that these standards were not proven to be "required” activities or services as contemplated by the Hancock Amendment. See Mo. Const., art. X, sec. 21; Miller v. Dir. of Revenue, 719 S.W.2d 787, 788 (Mo. banc 1986).
. Article X, section 3, provides that "taxes shall be uniform upon the same class or subclass of subjects;” section 4 contains multiple subsections addressing the classification of property for tax purposes and the percentage of "true value” that may be employed; and section 14 addresses the establishment of the State Tax Commission and provides that the Commission is "to equalize assessments as between counties."
The statutes that Plaintiffs argue violate SB287 include: section 138.380 ("Duties and powers of commission," setting out the Commission’s tasks regarding raising or lowering of assessed valuations and obtaining of related reports containing this raw data, among other tasks); section 138.390 (describing the Commission's duties regarding the equalization of valuations among the several counties); section 138.445 (concerning the Commission's duties related to a certification of the property valuations' annual report). Plaintiffs also allege violations of section 138.395, which, as relevant in 2004 set out the Commission's duties to report "equivalent sales ratios” for use in determining "equalized assessed valuations” factored into the school funding formula. Sec. 138.395, RSMo 2000 (repealed).
.Plaintiffs suggest that Department of Elementary and Secondary Education (DESE) acted irrationally by using the Commission's data. But, DESE was simply in the position of receiving data reported by the Commission. See Sec. 138.395, RSMo 2000 (repealed) (stating that the Commission shall certify the equivalent sales ratio to DESE).
. Moreover, even if the funding formula found in SB287 actually conflicted with earlier statutes, it does not follow that the current funding formula statute would be unlawful. See Turner v. State, 245 S.W.3d 826, 829 (Mo. banc 2008) (noting that where "two inconsistent statutes purport to be complete and independent legislation” the "later-enacted provision, even when there is no specific repealing clause, repeals the first statute to the extent of any conflict with the second”).
. These alleged flaws include the Commission’s assumption that assessment data from various counties were equalized among counties, without actually affirmatively equalizing the figures. See Mo. Const, art. X, sec. 14 (stating that the Commission is to equalize assessments among counties). Plaintiffs also point to the Commission’s use of "appraisal ratios” instead of "sales ratios” and its failure to use a certificates of value (COV) method for sales reporting. See Sec. 138.395, RSMo 2000 (repealed). There is no statutory requirement that the COV method be used in every county, but four counties currently do require its use. With this, they presented evidence that the Commission's property tax assessments did not in fact represent the "true value” of properties. See Mo. Const, art. X, sec. 4.