Phineas and Ferb: How Many Jellybeans?
Math → Geometry → Volume of Cylinder
Phineas, Ferb and friends try to determine the volume of a cylinder, but Buford solves it for them. This is a humorous introduction to the concept of volume of cylinders. There is a small little "bathroom humor" remark at the end to be wary of if you are dealing with a sensitive audience.