Congratulations to Mirah J. Dow, Jacqueline McMahon Lakin, and Stephen C. Court on their Kansas school library impact study titled School Librarian Staffing Levels and Student Achievement as Represented in 2006–2009 Kansas Annual Yearly Progress Data.  It was published in School Library Research, the AASL online journal, back in August 2012 and just came to my attention.  I believe it’s the first such study to use annual yearly progress (AYP) data–a significant landmark in this body of research.