If this is your first year working in a school library, this page has lots of good information to get you started. I suggest you get a binder or digital notebook and set up the following sections. As you print off/download and read an article, file it in the corresponding section. Jot down notes, how tos, and insights and file that as well. Over the course of time, you will be creating a How To Manual. Think how handy this would have been when you started. The librarian that follows you will be full of praise for your thoughtfulness!
School Library Policy is ultimately approved by the school board. The school librarian will work with the building administrator to craft the necessary policy and together, they will present it to the school board.
Policies establish a standard for services that can be understood by users of the service and providers. Policies ensure equitable treatment for all, and polices provide a framework for delivery of services.
Procedures are how you do things.
Rules are for behavior
A Handbook is usually one document that contains all the policies and procedures, plus an explanation on how the library runs.