You may be right. But the Equal Access Act might not provide much help to the OP in this instance. Under that Act a high school receiving federal funds and that allows a forum for groups to meet during noninstructional time is prohibited from denying any other group the same opportunity to meet during noninstructional time based on that group's "religious, political, philosophical, or other content of the speech". 20 U.S.C. § 4071(a). In short, once the school allows one group to meet after school hours it could not deny the same right to other groups to meet after school if that denial is based on the religious, political or other point of view of the group. So whether this Act is violated would again depend on the sort of details I asked about earlier. Note that the Act does not expressly provide any remedy whatsoever for the violation of the Act and expressly prohibits the federal government from withholding federal funds to schools who violate it. That would leave pretty much the only remedy here as being an injunction.