This Leadership Activities project will provide enhancement and professional development experiences for 50 nationally selected secondary school chemistry teachers in each of three years. The overall goals of the multiyear project involve the updating and deepening of the participants' chemistry backgrounds and teaching methodologies, the networking of the participants with university science faculty, the conduct of planned in-service workshops by the participants in their home schools and area colleges, appropriate recognition for honors- teachers participants, the dissemination of the project materials and results nationally, the investigation of the modelistic approach within a carefully planned documentation, assessment and evaluation effort. The summer leadership institutes will be held on the Princeton University campus. These will be staffed by four renowned university scientists/chemical educators and by an outstanding secondary school chemistry teacher with special expertise in computer applications to chemistry teaching. An advisory committee of distinguished scientists and educators will guide the planning of the program and the conduct of the evaluation and documentation activities. Participants will be encouraged to submit proposals for regional workshops conducted for other teachers; modest grants to support materials purchase and other costs will be available.