4. Discovery Education

free STEM lesson plansThe Discovery brand is known for its magazines and television programming, but it also offers resources to help teachers in the classroom through its Discovery Education site. Providing free STEM lesson plans for grades 6-8 and 9-12. The site’s content is organized into a variety of subjects, including science, math, technology, and business. Teachers can follow outlines for lessons covering the metric system, probability, and balancing a budget. In addition to offering engaging, free STEM lesson plans, Discovery Education also hosts virtual field trips, such as a Kilimanjaro Expedition, which is still available for viewing.