The first amendment of the US constitution suggests that the government shouldn't pass laws that "abridge freedom of speech." While public school boards (since

The first amendment of the US constitution suggests that the government shouldn't pass laws that "abridge freedom of speech." While public school boards (since 1982) have greater leeway in restricting what is available in schools, whether or not the first amendment is violated likely depends on the reason why a book has been banned. At least some of the books that are banned are considered classics of literature that have (for decades) been used in curriculums around the country (e.g., "Anna Karenina", "Catch 22", "Flowers for Algernon", etc.) The fact that you can get the books in libraries (which are also under pressure) or find them online is irrelevant -- it's a question of government power.