We present results from a randomized study of a well-defined use of computers in schools: a popular instructional computer program for pre-algebra and algebra. We assess the program using a test designed to target pre-algebra and algebra skills. Students randomly assigned to computer-aided...

Popular wisdom holds that publishers revise college textbooks mainly to kill off the secondary market for used books. While this behavior might be profitable if consumers are myopic, uninformed or have high short-run discount rates (that exceed the publishers'), neoclassical authors have noted...