I just purchased this movie. It runs about 30 minutes and teaches kids about the difference between 2 and 3 dimensions. The visual animation is very creative. Here’s the premise:
Flatland: The Movie is an animated film inspired by Edwin A. Abbott’s classic novel, Flatland. Set in a world of only two dimensions inhabited by sentient geometrical shapes, the story follows Arthur Square and his ever-curious granddaughter Hex. When a mysterious visitor arrives from Spaceland, Arthur and Hex must come to terms with the truth of the third dimension, risking dire consequences from the evil Circles that have ruled Flatland for a thousand years.