A National consortium of institutions is developing an innovative core calculus curriculum that is practical and attractive to a multitude of institutions. The consortium is led by Harvard University and in addition to that institution consists of the University of Arizona, Colgate University, Haverford-Bryn Mawr Colleges, the University of Southern Mississippi, Stanford University, Suffolk Community College, and Chelmsford High School. The refocus of calculus will use the "Rule of Three" whereby topics are explored graphically, numerically, and analytically.