Interactive
Curated OER

Student Exploration: Density Laboratory

For Students 4th - 6th
In this density laboratory worksheet, learners complete 2 prior knowledge questions, then use the "Density Laboratory Gizmo" to complete several activities, answering short answer questions when finished.
Interactive
PBS

Pbs Learning Media: Floating and Sinking: Hot Air Balloons

For Students 9th - 10th
Why do hot air balloons float? This resource from the NOVA Web site offers a series of interactive activities that illustrates the physics of hot air balloons.