This two-year project will address the difficulties presented by the transition from junior to senior high school mathematics by enhancing the mathematical and pedagogical skills of teachers in a setting which fosters cooperation between teachers at the two levels. Each year, forty underprepared teachers -- half from grades 7 and 8, and half from grade 9 -- will participate in a six-week summer workshop that includes courses in probability and statistics, as well as a seminar on issues in mathematics education. Each junior high teacher will work jointly on a project with a high school teacher. The academic-year follow-up consists of classroom visitations by the project staff and nine workshop-seminars for participants. The project will enable participants to use probability and statistics as a means of reinforcing basic skills while developing their students' higher-order thinking skills. It also provides a model of constructive interaction between junior and senior high school teachers. The project represents a collaboration between the University of Alabama at Birmingham and the Birmingham Public Schools, each of which contributed significant cost-sharing to the project.