We bears don't mess with nature, and we don't put up with nonsense either. Nature doesn't jest, so we prefer to homeschool our cubs. Nature is way better than a physics lab. They learn fundamental physical laws just by watching salmon jump upstream in the fall. A salmon's leap describes a parabolic trajectory determined by its initial speed, for a start. These fish have an amazing ability to swim upstream by taking advantage of the eddies that form in the water. Salmon strategically place themselves in areas where vortices create a push they can use to their advantage, allowing them to move forward with less effort. But beyond the school curriculum, we love to watch the cubs see their reflection in the water for the first time. We wouldn't miss it for the world. You won't find that in any textbook.