Actually to be a school librarian you only need a bachelor's of education focusing in something IT-related, plus whatever teaching cert your state requires. And in public libraries, you also only need a bachelor's in information science to be a library tech, which is the one that stocks the shelves and checks out books to local schoolchildren. Only being a full librarian needs a Master's. That said, academic libraries won't even look at you if you have less than a Master's.