Illinois State University seeks funds to develop a model mathematics program for elementary teachers grades K-6, both preservice and inservice, focusing on the cognitive guided instruction approach to instruction. Teams of experienced teachers will be selected and prepared in CGI for a year and these teachers will establish learning environments in their classrooms that reflect current research findings on how children learn mathematics. Subsequently, these teachers and new teams will work with preservice teachers in mathematics and mathematics education required coursework and school-based experiences. The preservice teachers will be in seminars together with the inservice teachers. These seminars will address teaching and learning as related to problem solving with understanding in the topic areas of the Curriculum and Evaluation Standards of the National Council of Teachers of Mathematics. The preservice teachers will be studied in the research component of the project as they become new teachers and are followed by the proposers into their own teaching years throughout the duration of the project. The College of Education and the Department of Mathematics are collaborating in the implementation of this program together with school systems in the area. The contribution of Illinois State University accounts for 22% of the NSF budget.