The Physics Front is a free site that contains teaching resources on Physics and Physical Science. The resources are searchable and are arranged by level: K-8 Physical Science, Physics First, Conceptual Physics, Algebra Based, and AP / Calculus. Resources are then organized by topic.
It's part of the ComPADRE education community resources.
There are lesson plans, links to other resources, technology, links, and other resources to help educators when teaching Physics or Physical Science. It's another great resource to add to your collection.
MyPhysicsLab - Free Physics Simulations
PhET - excellent, free, virtual labs and simulations for science
Physion - free Physics Simulation Software
Great Physics Resources for Students and Teachers