The GK-12 program of the National Science Foundation is an innovative program for enriching the value of graduate and advanced undergraduate students' education while simultaneously enriching science and mathematics teaching at the K-12 level. GK-12 is a fellowship program that offers graduate students and advanced undergraduates the opportunity to serve as resources for K-12 teachers of science and mathematics. An evaluation was conducted to provide information about GK-12. One component of the evaluation was the qualitative analysis of case studies from 12 purposively selected sites, and the other was a quantitative analysis of survey data from all project sites. Findings show that the areas most often cited as strongest program areas were: (1) content knowledge gains for teachers; (2) positive role models for students; (3) improved school-university relationship; and (4) improved communication and instructional skills of Fellows. The two areas most often cited as "less strong" were: (1) clarification of the Fellows' and teachers' roles; and (2) summer training. The most often cited implication for the GK-12 Program as a whole was sustainability. Overall, the program appears to be meeting its goals. To provide better information, surveys are being conducted of all Fellows, about 1,000 cooperating teachers, about 1,000 graduate students not receiving GK-12 support, and school district staff in participating school districts. (SLD)