If it's necessary for school librarians to also be certified teachers. Then why are kids successfully taking their homework to the public library.

If in fact being a state certified teacher was an absolute imperative, to being a successful school librarian. Then how is it that children's librarians at the public library, as well as skillful public librarians are successful, in not only providing bibliographic instruction to children and young adults. But also they're successful in supporting school curriculum by helping these school children and young adults with their homework assignments, and with their thoughtful library collection development and collection maintenance. May we proffer the proposition that in fact skillful public librarians and librarians serving children and young adult populations are in fact already functioning defacto school librarians.