The education Research Center at the Massachusetts Institute of Technology (formerly the Science Teaching Center) was established to study the process of instruction, aids thereto, and the learning process itself, with special reference to science teaching at the university level. Generous support from the National Science Foundation and from the Kettering, Shell, Victoria, W. T. Grant, and Bing Foundations provided the means for assembling and maintaining an experienced staff to cooperate with members of the Institute's Physics Department in the examination, improvement, and development...