This study investigated teachers' motivation, expectations, and changes to teaching practices due to a 6 week summer professional development program involvement. Participants (n = 67) attended the Research Experiences for Teachers (RET) program within a major university in southeast. Surveys and interviews were used to collect data to answer the following research questions: (1) Who attends the RET program? (2) In what ways do elementary teachers differ from middle/secondary teachers with respect to their motivation for attending the RET program and their expectations about the program? (3) In what ways do elementary teachers differ from middle/secondary teachers with respect to implementing changes to their teaching practices due to RET program attendance? Survey results indicated significant differences between elementary teachers and secondary education teachers with respect to their expectations about the program, and changes to their teaching practices. Interview results provided support to survey findings. Implications for professional development and science teacher education are discussed in relationship with the current study findings.