Collaborative professional development of science and special educators leads to improved access and inclusion of students with disabilities. Yet, despite poor science achievement of students with disabilities, their increasing presence in general education science classrooms, and research that demonstrates effective teaching strategies for students with special education needs, there have been few reports of joint professional development in the literature. The purpose of the study was to examine changes in the teaching practices of science and special educators, grades 4 to 8, as they completed an intense year-long professional development program designed to promote hands-on, inquiry-based science in their classrooms and expand their instructional repertoires to better serve students with disabilities and other learning problems. Quantitative and qualitative measures, including pre and post ratings of teacher classroom performance, action research projects, and teacher self-reports were used to determine changes in teaching practices. Findings indicated all teachers showed improvement in the classroom on many elements related to classroom culture, instructional content, and lesson design and implementation, and the ability to adjust instruction.