Is there any case law where a school has been found to have discriminated against a student because of their first amendment values?

Clearly, mere reference by a defendant to personal standards of taste or political philosophy as one factor in a decision involving first amendment values cannot, in and of itself, provide a basis for rationally inferring an intent to suppress the different views of others. Courts cannot prohibit and, indeed, should encourage, within limits, the thoughtful application of personal standards of taste and morality and of political belief in the performance of governmental functions. Where, however, as in this case, evidence that the decisions made were based on defendants' moral or political beliefs appears together with evidence of procedural and substantive irregularities sufficient to suggest an unwillingness on the part of school officials to subject their political and personal judgments to the same sort of scrutiny as that accorded other decisions relating to the education of their charges, an inference emerges that political views and personal taste are being asserted not in the interests of the children's well-being, but rather for the purpose of establishing those views as the correct and orthodox ones for all purposes in the particular community. What was said in Village of Arlington Heights v. Metropolitan Housing Development Corporation, 429 U.S. 252, 267, 97 S.Ct. 555, 564, 50 L.Ed.2d 450 (1977), applies here: