A huge investment in public funding, approximately 10 million dollars for the 2002 fiscal year, has been dedicated to the implementation of the National Science Foundation's (NSF's) Graduate Teaching Fellows in K-12 (GK-12) program. In these GK-12 programs, graduate level scientists known as Graduate Teaching Fellows are placed in K-12 science classrooms to act as resources for science teachers. The NSF's investment is aligned with reform documents which call for scientists and the science education community to work together to realize the goal of scientific literacy for all. Although much research has been done on factors that influence science teachers' views of science and ultimately the way science teachers interpret and deliver science content, little research has been done on the impact that this type of program will have on science teachers' teaching practice. The purpose of this research is to examine the impact on the science teachers involved in a NSF GK-12 program. This program was implemented at a large Southeastern university and the local school district. Data were collected on one cohort for one academic year using qualitative methods of observation and interviews. The findings of this research highlight the need to examine in more depth three groups influenced by these collaborations: the science teachers, their students, and the scientists. (Contains 20 references.) (Author/MVL)