This document discusses key aspects of effective science teacher training and professional development. It outlines that science teachers must have a strong knowledge of their subject matter and understand how to plan instruction. They also need to understand how students learn and how to meet the needs of diverse learners. Effective teacher learning opportunities, such as communities of practice and reflective dialogue, can help teachers continually improve. Professional development programs should focus on hands-on learning, understanding students' perspectives, and engineering better instruction - including support for English language learners. When teachers receive these types of learning opportunities, it can improve student achievement and reduce inequities.