Does this law apply for students of all ages? Surely "sexually explicit" materials are a requirement for sexual education right? What am I missing?
You're missing that most of these people want to kill sexual education too. They are openly against modern education, and think the father of the household should have final say on anything and everything.
There's an overlap between these sort of hyper-reactionary people and politically motivated street toughs, who are likely to keep escalating such situations because it's strategically effective.