Connected Mathematics is a complete middle school mathematics curriculum developed by Connected Mathematics Project (CMP). The aim of CMP has been to help students and teachers develop understanding of important mathematical concepts, skills, procedures, and ways of thinking and reasoning, in number, geometry, measurement, algebra, probability and statistics. CMP is based on research, and was field-tested in diverse sites across the country with approximately 45,000 students and 390 teachers. Each unit, in both 1991-1996 and 2000-2006 development periods, went through at least 3 cycles of field testing. Supported during its development by the National Science Foundation, one link is to the publisher's website and another is to the project development site.