This study measured the impact of teacher professional development (PD), designed to support grades 3-5 integrated science activities in Indiana, United States and enhance mathematics and language arts learning experiences. To determine whether students of the Indiana Science Initiative (ISI) teachers benefitted, we conducted a matched comparison study of 1546 classrooms using multi-level modeling to identify the effect of teachers on their students’ science, English Language Arts, and math state assessment scores. Results show that when teachers participated in multiple years of ISI and attended PD recently, their students had statistically higher standardized test scores than the comparison group in science as well as mathematics and ELA.