Above animation is by Megan Hendershot
The fist animation of a bouncing beach ball there could be a bit more stretch in the balls ascent and decent. The fall of the beach ball in the beginning could have arched forward a little more. The first hit of the ball on the floor does not squash but has the bottom of the ball disappear into the floor. The second bounce when ascending is going more in a line straight up than an arc. The ball appears to fall and rise a bit to evenly there could be a little more increased speed in the ascent and at the peek of the arc there could be a bit more decrease in speed to show the slowing down as the ball begins its decent.
The second animation of a smaller ball could first have the last few frames spaced out some to slow down the bounces at the end to show the decrease in energy. Again like in the first animation there could be a little more stretch in the rise and fall of the ball. In the first bounce off the floor around 00:03 the arc seems to be good till right before the top of the arc where the ball jumps just a tiny bit up in the arc.
Though there are some miner problems the overall work on the animations was good. Just have to work on deviating from the reference video to create a great squash and stretch in the ball and added a little more variation in the spacing of the frames to show increase and decrease in speed. Overall the animations just need a little more work but are great for starters.