Classroom and School Library--What's the Difference?

I was reading through some of my library school material recently and came across this passage. It helps explain the special role of a school library....and, I think, why they need to be supported.

"A school library and a classroom collection of reading material both support the school reading program. One cannot substitute for the other. One--the school library is a collection of resources that are organized according to a standard system with materials catalogued and classified for universal accessibility. The other--the classroom collection of reading materials--is organized and leveled to service the individual classroom.........

By providing proactive support for in-class reading instruction, school library media specialists demonstrate their commitment to helping schools meet reading goals. For teachers, they provide catalogued sets of material in searchable formats and data on material use. For students they provide collections for research, skill building, and pleasure that support reading motivation."

Roscello, F. and P. Webster (2002). Characteristics of School Library Media Programs and Classroom Collections: Talking Points, Albany, NY: Office of Elementary, Middle, Secondary and Continuing Education, New York State Education Department.