This .pdf resource is the presentation used by Dr. Johnell Bentz for her breakout session titled "Differentiating Instruction in your Classroom" at the 2011 INTC Beginning Teacher Conference.
The Lexile Framework for Reading website provides an online tool for submitting sample text from a textbook, a novel, or questions you've created for a test or quiz.
The American Institutes for Research and researchers from Vanderbilt University and the University of Kansas -- through funding from the U.S.