The Board cannot escape its obligation to honor parents’ free exercise rights by deliberately designing its curriculum to make parental opt outs more cumbersome.The Board also suggests that permitting opt outs from the “LGBTQ+-inclusive” storybooks would be especially unworkable because, when it permitted such opt outs in the past, they resulted in “unsustainably high numbers of absent students.” Id., at 12. But again, the Board’s concern is self-inflicted. The Board is doubtless aware of the presence in Montgomery County of substantial religious communities whose members hold traditional views on marriage, sex, and gender. When it comes to instruction that would burden the religious exercise of parents, the Board cannot escape its obligations under the Free Exercise Clause by crafting a curriculum that is so burdensome that a substantial number of parents elect to opt out. There is no de maximis exception to the Free Exercise Clause