Teachers of the science students participated in three weeks of summer professional development (PD) at a
Midwestern university that was taught by university professors and a high school science teacher. The PD focused
on student-centered instruction and inquiry (Lawson, 1995). The student-centered pedagogy modeled by
investigators to improve participants’ pedagogical knowledge included active laboratory investigations. Teachers
explored content areas of physical science, life science, earth science, and environmental science through
approximately 30 inquiry-based lessons that addressed Missouri Grade Level Expectations and Course-Level
Expectations (Missouri Department of Elementary and Secondary Education, 2008) to improve participants’
content knowledge. To encourage teachers to implement student-centered instruction beyond the summer PD, each
teacher received a classroom materials kit with the corresponding lesson plans. Participant teams developed
instructional units for action research to measure the impact of professional development. During the fall of the
next school year, they were asked to implement the unit of instruction over a period of three weeks.