Figuring out how the animation will work is not so hard ... 7. Now we are going to animate the ball and make it bounce up and down. Click on frame 30, right-click and select 'Insert Frame' to extend ...

Here's how to get more bounce from a normal tennis ball - buddy it up with a heavier ball for twice the impact. Hold a ball in each hand and decide which ball weighs more (has greater mass).

There’s still one small mystery, however. Every now and again, [T-Kuhn] says that the ball will bounce in an unexpected direction. It doesn’t seem to be a bug related to the platform itself ...