Discussed are the origins, objectives, activities, and achievements of a project which developed a book of lessons to teach high school students about the U.S. Constitution. A textbook study and an educational conference revealed the need to develop supplementary curriculum materials to strengthen textbook treatments of the Constitution. The book of lessons was created according to established procedures in curriculum development: (1) conceptualization; (2) creation and evaluation of prototype lessons; (3) creation and evaluation of a complete collection of lessons; and (4) revision of lessons based on field tests and critical reviews. Contributions of teachers, scholars, and curriculum specialists were many and included providing lesson ideas, checking accuracy of material, and contributing knowledge about course organization. The scholars were also involved as critical reviewers of the lessons. Examples of their generally positive reviews are provided. The main achievement of the project was the book of 62 lessons entitled "Lessons on the Constitution: Supplements to High School Courses in American Government and History." Evidence gathered from field test teachers indicates that the lessons are practical and do work. Dissemination activities included 12 workshops and conferences. (RM)