I've started teaching experimental animation at the Academy of Art University in San Francisco, which includes an introduction to clay animation. The animation above is a demo of part of the assignment that uses replacement animation. Using equal amounts of clay for each stage, students create this series:
But the demo above would receive nothing more than a C, as it just barely accomplishes the objective and is hardly creative. The goal is to take this animation concept and run with it, as this one demonstrates in spades from Danny of SJproduction. Not sure if he uses replacement animation, but the principle of the jump is there.
So if you want to explore clay animation but don't want to get into armatures and lip sync yet, this is a good place to start. Just start by bouncing the ball around and see where your imagination takes you.