Make a Cold Front with a Density Tank
Use the Make a Cold Front with a Density Tank video with Lesson 9: Step 2, What causes precipitation along a cold front? of the GLOBE Weather curriculum.
This is a slow-motion video of cold fluid and warm fluid interacting in a density tank to demonstrate what happens at a cold front, where a cooler air mass and a warmer air mass interact in the atmosphere. The cold, dense air sinks towards the surface and pushes the less dense, warm air, causing it to rise high into the atmosphere.