Recently South Carolina came out with a school librarian impact study.

Quick Link to the study reports: 
Phase I report and Phase II report.

Results you need to know:

The Palmetto Assessment of State Standards (PASS) results were examined for all elementary and middle schools that responded to the 2013 South Carolina School Library Survey. For all students, excellence on PASS standards was associated with the following characteristics of school library programs:

• Having at least 1 full-time librarian and a full- or part-time library assistant
• Spending $7,500 or more annually and $13.33 or more per student
• Logging 20,000 or more checkouts and 36 or more items per student
• Providing access to 40 or more e-books
• Having public access computers in the school library and 18 or more (versus fewer than 6) elsewhere in the school
• Receiving 4 or more group visits per week.
• Having a librarian who teaches information literacy 20 or more hours per week
• Having a print collection of 13,000 items or more (versus fewer than 7,500 items)

The High School Assessment Program (HSAP) results were examined for all high schools that responded to the 2013 South Carolina School Library Survey. All students were more likely to meet HSAP standards and to perform at the proficient level or above, if their schools had:

• At least 1 full-time librarian
• At least 2 full-time librarians
• At least 1 full-time library assistant
• Total library expenditures of $12,500 or more
• Total circulation of 7,500 or more checkouts
• Total print collection of 11,000 or more items
• Total e-book collection of 70 or more titles
• 15 or more group visits to the library per week

Where does your school stand regarding these characteristics? If you couple this with the recent Washington state study school libraries can make their case even stronger!

Image credit: http://tinyurl.com/pt386qp, licensed under CC BY 2.0