I've made a very simple example of a 3D scene using my 3D java renderer. Playing with that will give you an example to start with, when you make your own things with my 3D renderer.
First, download the source files from that example, as well as the source files for the render package, and make sure you can compile and run things.
Your assignment is to make some sort of simple animated thing with my 3D renderer. It can be a house, a tree, a porcupine, or a nucleic acid. Feel free to be creative. Have fun with it.