We have a librarian at my school only 2-1/2 days a week, as she must split her time between 2 high schools. When she's not there, parent volunteers staff the library so that it's available to students.
A union grievance was filed, and today we were told that the library cannot be open anymore when she's not there. Teachers can take their classes in there, but books cannot be checked out. The library will no longer be available for students to do make-up tests in on the days when our official librarian isn't on site.
The next time a teachers union tells you something is "for the children", you remember this story.