First Cannonball?

Tonight was Jack's bath night. He loves his bath and likes to play with toys, splash and get squirted by his squirty toys. But tonight, he figured out something new. He kept standing up and then plopping down (which is not so worrysome since we have an inflatable toddler tub) to see how much he could splash. At first I thought it was an accident but when he kept doing it, I realized that this must be what a baby cannonball looks like.