Does Teacher Professional Development Affect Content and Pedagogical Knowledge: How Much and for How Long? CSE

We examine the impact of teacher professional development on knowledge growth and subsequent knowledge retention. Specifically we use English Language Arts teacher content and pedagogy assessments to determine whether the California Professional Development Institutes significantly improve teacher content knowledge and whether teachers retain that knowledge six months after the institutes are completed. The results indicate that teachers vary significantly in pre-institute knowledge on the four assessed domains, demonstrate significant knowledge growth, but only retain about one half of what was gained during the institute. Further, pre-existing knowledge gaps are not systematically reduced and teacher perceptions of institute quality are not related to knowledge growth and knowledge retention. Current No Child Left Behind (NCLB) legislation requires that all students are taught by highly-qualified teachers (NCLB, 2001). The logic of NCLB and related state and district policies is straightforward; to make adequate progress towards proficiency in the core subjects of English language arts and mathematics, students need to receive instruction from teachers who are well-prepared to teach these subjects. Teacher professional development is widely viewed as the most promising intervention for improving teacher quality in U.S. public schools. Nearly every state and district provides inducements for teachers to participate in professional development and these are increasingly supplemented by federal programs such as Reading First. Districts often add requirements on top of these, either in the form of mandatory programs for all instructional staff, or by requiring time investment beyond state requirements. The