This STEM Professional Development module for teachers looks at solar system-related topics in middle school Earth and Space Sciences, including the definition and boundaries of the solar system, its components, size and distances, orbits, causes of seasons, and relevant technologies. Teachers using the self-paced interactive lesson can learn or review science content and pedagogy while using NASA media found on PBS LearningMedia, which you can then readily use with your own students.This resource is part of the NASA Planetary Sciences Collection.