This study measures changes in teaching practices that occurred during a school year that included laptop implementation and professional development. The changes were documented through direct observations of more than 400 classrooms in more than 50 K-12 schools in 11 Florida districts. Trained observers used two valid observation instruments to measure teaching practices and technology use. The Mantel-Haentzel procedure was used to infer statistical differences between fall and spring observations. Observed percentages, means, standard deviations and effect sizes are provided. Results suggest laptop implementation and professional development can lead to increased student-centered teaching, increased tool-based teaching, and increased meaningful use of technology. This research suggests that laptop implementation coupled with professional development may have an immediate impact on instructional practices. (Contains 4 tables.)