dissenting:
The parental enforcement provision of Proposition 227 allows parents to sue California’s public school teachers for money damages for their use of non-English1 without providing the teachers with sufficient clarity as to how much English is required and in what circumstances and settings. As a result, educators fearing personal liability must either teach at their own risk or, as is more likely, acquiesce in the complete elimination of non-English in the performance of their duties. Because the provision here raises all three concerns underlying the First Amendment vagueness doctrine — a lack of fair notice, a threat of ad hoc and subjective enforcement, and a chilling effect on protected expression — I must respectfully dissent from the majority’s holding that the parental enforcement provision is not void for vagueness.
“First Amendment rights, applied in light of the special characteristics of the school environment, are available to teachers and students. It can hardly be argued that either students or teachers shed their constitutional rights to freedom of speech or expression at the schoolhouse gate.” Tinker v. Des Moines Indep. Sch. Dist., 393 U.S. 503, 506, 89 S.Ct. 733, 21 L.Ed.2d 731 (1969). In light of the special charac*1156teristics of the school environment, however, the government can more readily regulate teacher speech in school-sponsored expressive activities because of the state’s interest in educating students. See Hazelwood Sch. Dist. v. Kuhlmeier, 484 U.S. 260, 267 and 272-73, 108 S.Ct. 562, 98 L.Ed.2d 592 (1988) (holding that the test for limiting student speech is whether the restrictions are “reasonably related to pedagogical concerns” but also approving of “reasonable restrictions on the speech of students, teachers, and other members of the school community”); Downs v. Los Angeles Unified Sch. Dist., 228 F.3d 1003, 1010 (9th Cir.2000) (suggesting the “same principles” of Hazelwood would govern regulation of teacher speech). Thus, the First Amendment applies in the schoolhouse and the school yard. Presumably the majority agrees, concluding that “Proposition 227 clearly implicates free speech rights.” See Maj. op. at 1149. We have repeatedly recognized in no uncertain terms that “[wjhere the guarantees of the First Amendment are at stake the [Supreme] Court applies its vagueness analysis strictly.” Cohen v. San Bernardino Valley Coll, 92 F.3d 968, 972 (9th Cir.1996) (quoting Bullfrog Films v. Wick, 847 F.2d 502, 512 (9th Cir.1988)). Unfortunately, the majority fails to do so here.
As an initial matter, the majority construes the scope of Proposition 227’s language restrictions, and hence the basis for the potential liability of educators, as limited “to the language of instruction, i.e., the language teachers use to present the curriculum to students in California public schools.” Maj. op. at 1151. Assuming that it is sufficient simply to note that “instruction” and “curriculum” are “words of common understanding,” the majority then asserts that such an interpretation would include the teaching of academic lessons, but not other forms of interaction between teachers and their students. Maj. op. at 1151-52. Yet these terms have been recognized as having a far broader meaning than the majority is willing to recognize by none other than the United States Supreme Court itself:
The question whether the First Amendment requires a school to tolerate particular student speech — the question we addressed in Tinker — is different from the question whether the First Amendment requires a school affirmatively to promote particular student speech. The former question addresses educators’ ability to silence a student’s personal expression that happens to occur on the school premises. The latter question concerns educators’ authority over school-sponsored publications, theatrical productions, and other expressive activities that students, parents, and members of the public might reasonably perceive to bear the imprimatur of the school. These activities may fairly be characterized as pari of the school curriculum, whether or not they occur in a traditional classroom setting, so long as they are supervised by faculty members and designed to impart particular knowledge or skills to student participants and audiences.
Hazelwood, 484 U.S. at 270-71 (emphasis added).
Thus, while the term “curriculum” has been construed broadly for purposes of defining the authority of the state to regulate school-sponsored expression that could reasonably bear the imprimatur of the school, when it comes to saving this ambiguously worded restriction on the use of non-English by teachers the majority asserts that the provision is readily susceptible to a narrowing construction that is contrary to the Supreme Court’s own understanding. Nor, as the majority concedes, can this court authoritatively construe the enforcement provision and give it a narrowing construction, which is a mat*1157ter of state law.2 It is no wonder, then, that plaintiff teachers are concerned about the use of non-English in such circumstances as student tutoring, field trips, supervision, and discipline.3
Even assuming that the scope of Proposition 227 is readily susceptible to some narrowing construction that would make it sufficiently clear to survive strict vagueness scrutiny as to when the use of non-English is restricted, I cannot agree that terms such as “overwhelmingly” and “nearly all” provide teachers with ample certainty as to how much non-English could expose them to personal liability. The majority states that although terms such as these “are not readily translated into a mathematical percentage, the First Amendment does not require them to be.” Maj. op. at 1152. I agree. We should not ignore, however, as the majority does, the fact that individual school districts have interpreted these terms as requiring anywhere between 60 and 90 percent English.4 While mathematical certainty may not be required, some modicum of objective clarity is constitutionally necessary. It is well settled that “[a] statute must be sufficiently clear so as to allow persons of ‘ordinary intelligence a reasonable opportunity to know what is prohibited.’ ” Foti v. City of Menlo Park, 146 F.3d 629, 638 (9th Cir.1998) (quoting Groyned v. City of Rockford, 408 U.S. 104, 108, 92 S.Ct. 2294, 33 L.Ed.2d 222 (1972)). Holding that the terms “nearly all” and “overwhelmingly” are sufficiently clear, in light of the disparity of interpretation adopted by public school districts throughout California, necessarily impugns the “ordinary intelli*1158gence” of our school officials in a manner that I find unwarranted.
The majority then contends that because teachers have an affirmative obligation to impart knowledge to their students and because they may even be required to use non-English in certain situations by their employing school districts, “it is highly unlikely that educators will restrict themselves to speaking English only.” Maj. op. at 1152. The majority is apparently oblivious to the dilemma in which this places teachers of either fulfilling their legal and professional duties and exposing themselves to liability, or ignoring their teaching obligations in order to steer clear of a vague restriction on the amount of non-English that is permitted. Cf. Baggett v. Bullitt, 377 U.S. 360, 374, 84 S.Ct. 1316, 12 L.Ed.2d 377 (1964) (“The State may not require one to choose between subscribing to an unduly vague and broad oath, thereby incurring the likelihood of prosecution, and conscientiously refusing to take the oath with the consequent loss of employment, and perhaps profession, particularly where the free dissemination of ideas may be the loser.” (Internal quotation marks and citation omitted)). Under such circumstances, the use of non-English would only reflect a state-imposed professional duty that compels teachers to put themselves in jeopardy of liability to parents.
Moreover, contrary to the assertion of the majority, the amount of non-English foregone by teachers fearing liability is not negligible. Assuming the terms “nearly all” and “overwhelmingly” could be interpreted, as the facts show they have been, to require anywhere between 60 and 90 percent English, then the amount of chilled non-English could very well represent between 10 and 40 percent of expression by teachers. Surely, by any measure, this amount of deterred expression constitutes a sufficiently real and substantial chilling effect of a substantial amount of legitimate speech for the purpose of strict vagueness scrutiny.
The majority suggests that any vagueness is ameliorated by the inclusion of a scienter requirement. However, “[a] scienter requirement cannot eliminate vagueness ... if it is satisfied by an ‘intent’ to do something that is in itself ambiguous.” Nova Records, Inc. v. Sendak, 706 F.2d 782, 789 (7th Cir.1983). What does it mean “wilfully and repeatedly” to refuse to implement the terms of Proposition 227 by not providing “an English language educational option,” when the amount of permissible non-English is not authoritatively defined and is in fact so imprecise that individual school districts have such widely varying interpretations? The majority believes “[i]t is sufficient to note that we seriously doubt such wrongful intent could be found if an educator in good faith attempts to comply with Proposition 227 or in good faith attempts to comply with the school district guidelines regarding the language of instruction.” Maj. op. at 1154. But school district guidelines are of no help when the officials promulgating those guidelines are accountable to parents for the implementation of “an English language educational option” — the enforcement provision at issue specifically targets school board members, elected officials, and administrators, as well as teachers. Will a teacher be held liable when she “wilfully and repeatedly” teaches under a 60 percent guideline imposed by the school board, even though warned by the parents of a student that they consider that inadequate? Does adherence to such a guideline constitute “good faith” even when the officials of the school district may be sued as well? Must she disobey to show “good faith,” despite her obligation to teach in conformity with official school district policies and guidelines? 5
*1159The mitigating effect of the scienter requirement is diluted not only by the futility of attempting to determine what it means to intend to do something as vague as “refuse[ ] to implement the terms of this statute by providing an English language educational option,” but also by the fact that it is the parents, not any governmental authority, who wield the prosecutor’s enforcement discretion.6 Section 320 presents a real risk of subjective and ad hoc enforcement precisely because it is left to the discretion of individual parents and their own disparate notions of what constitutes “an English language educational option.” Regardless of what the school district requires, the parents of any individual student may hold the threat of personal liability over any teacher who they contend refuses to implement the vague terms of Proposition 227. The threat of such ad hoc enforcement is alone sufficient to chill the use of non-English, despite any residual comfort that, at the end of the day, a teacher may not be held liable. Because it is unclear when (in what settings) the language restrictions apply and how much English is required, Proposition 227’s parental enforcement authority is “so imprecise that discriminatory enforcement is a real possibility.” United States v. Wunsch, 84 F.3d 1110, 1119 (9th Cir.1996).
Despite the majority’s hyperbole, plaintiff teachers need not establish that the terms of Proposition 227 are “unfathomable,” “boundless,” or “incomprehensible.” Notably, not even appellees have argued that the terms “nearly all” and “overwhelmingly” would survive the strict vagueness scrutiny that the First Amendment commands.7 Yet the majority so concludes. Teachers do not have fair notice of when and how much English is required to avoid personal liability; delegation of enforcement to the whims of individual parents invites ad hoc and subjective enforcement; and the vague terms of the provision result in a real and substantial chilling effect on expression within the ambit of First Amendment protection. The parental enforcement provision of Proposition 227 allows for what can best be described as a means of “legalistic ambush.” Cohen, 92 F.3d at 972. “If teach*1160ers must fear retaliation for every utterance, they will fear teaching.” Ward v. Hickey, 996 F.2d 448, 453 (1st Cir.1993). For the foregoing reasons, I dissent.
. I use the term "non-English” as a shorthand expression to mean any and all languages, e.g., Spanish and Vietnamese, other than the English language.
. The majority contends that its construction is supported by an intermediate state appellate court decision, McLaughlin v. State Bd. of Educ., 75 Cal.App.4th 196, 89 Cal.Rptr.2d 295 (1999). See Maj. op. at 1147. That decision, however, did not even concern the scope of Proposition 227’s language requirement; it thus lacks any analysis of the scope of Proposition 227. Further, its passing references to "instruction” provide no indication of whether the term is limited to academic lessons, or also includes other classroom activities and non-classroom curricular activity. Finally, in the passage that the majority removes from the context of the decision, the state court also refers to "English-only” instruction — yet it is the very ambiguity of how much English is required by terms such as "overwhelmingly” and "nearly all” that is at issue here. No party contends that Proposition 227 requires only English. It is thus doubtful whether the cited passage supports much of anything for our purposes here.
. The broad scope of circumstances under which a teacher might be sued for using non-English is further underscored by the vague and encompassing variety of alternative phrases employed within the text of the enforcement provision itself: "English language public education,” "English language instructional curriculum,” and "English language educational option.” See Cal. Educ.Code § 320. Even if, as the majority asserts, the use of these terms "is simply a shorthand to the core requirements of Proposition 227 embodied in sections 305 and 306,” majority op. at 1147, those sections do not lend themselves to the construction adopted by the majority. Section 306(d), for example, in defining "sheltered English immersion,” specifically distinguishes between "classroom instruction” and "curriculum and presentation.” Moreover, despite the majority's effort to cabin the potential scope of teacher liability under § 320, it is interesting to note that appellees themselves disagreed below as to the scope of the provision's requirements. Defendant State Board of Education and its members insisted that the language restriction applied to "only classroom communication, and more specifically classroom instruction,” whereas Interve-nor Ron Unz, the sponsor of Proposition 227, contended that "[t]here is no reason (as the SBE suggests) to limit the applicability of Section 320 to the classroom.” Confusion of this sort is a further indication that teachers will continue to remain uncertain of when such language restrictions apply.
.See Louis Sahagun, Responses to Prop. 227 All Over the Map, Los Angeles Times, September 2, 1998, at B2, available at 1998 WL 18870286.
. These concerns are not hypothetical. For example, the declarations of the plaintiff *1159teachers indicate that some school districts require the use of a “preview/ review” method of teaching whereby a teacher "previews” a lesson by giving her students vocabulary words and concepts in Spanish, teaches the lesson in English, and “reviews” the students’ comprehension of the lesson in Spanish. If a teacher believes that this method may be inadequate under Proposition 227 or is warned to such effect by a parent, what is she to do when her school district has interpreted it as permissible under the vague terms of the provision and requires that it be used? Does that mean she, or the school board officials for that mattei', are attempting to comply in "good faith”?
. The State Board of Education has the authority to promulgate regulations clarifying when and how much non-English is permissible for the benefit of all concerned-parents, as well as school officials and teachers. Under state law, it has the authority to "adopt rules and regulations not inconsistent with the laws of this state ... for the government of ... elementary schools ... and ... secondary schools ... of the state.” Cal. Educ.Code § 33031. In fact, the State Board of Education has promulgated regulations clarifying other aspects of Proposition 227, such as the terms "a good working knowledge of English” and "reasonable fluency in English” from §§ 305 and 306. See Cal.Code Regs. tit. 5, §11301. It has not seen fit, however, to provide a uniform standard establishing when and how much English is required under Proposition 227 to avoid personal liability.
. In fact, appellees readily concede that “[r]esolution of this issue will turn largely on the Court's choice of the proper standard of vagueness scrutiny to be applied to the statute.” Appellees contend that ordinary due process scrutiny is all that is required because no protected First Amendment interests are at stake. The majority rejects that analytical premise, but nonetheless upholds the provision.