"Launch rockets, build robots, explore your world and beyond! Our projects, toolkit and contests will take you into space without ever leaving Earth." Maintained by the lab at NASA, this collection of activities and learning resources for curious K-12 students will engage and inspire students to explore space and other sciences. Content is filterable by grade level, and teacher resources are also found on the site.
PhET provides fun, free, interactive, research-based science and mathematics simulations. Students engage in simulations related to physics, chemistry, earth science, math, and biology. Students, teachers, and parents can find plenty of instructional information for teaching with the simulations, too.