The program will consist of a three-week summer institute for 35 high-school biology teachers in each of two academic years (for a total of 70 teachers), with 2 two-day follow-ups during the academic year. The program is designed to (i) prepare, or enhance, the teachers' knowledge of the nature of scientific inquiry, using the theory of evolution as the content subject; (ii) to encourage teachers to begin their biology courses with the topic of evolution and the nature of science, using them as central themes to integrate the remainder of the topics; (iii) to help the teachers to develop a dynamic, self-correcting method for becoming more effective, through formative and summative evaluation of both teaching courses. The institutes will be presented in a variety of modes including lectures, demonstration, films, discussions, field trips, etc. The follow-ups will increase appreciably the extent to which changes in content and curriculum are actually incorporated, and will allow further development of self-correcting implementation program. Both formative and summative evaluations of teachers and courses will encourage a self-correcting approach to change. An amount equivalent to 14.5% of the NSF award is being contributed by Indiana University as cost sharing. The NSF cost per participant for the project is $4,308 in the two years' duration.