Earth and Moon
This is a simulation of a reduced two-body problem.
I have used data for the Earth and the Moon just to make
it more attractive . The rotation is simulated using animated gifs.
However, in slow machines, this can unnecesarily waste some computer
resources. Hence, if the simulation behaves strangely, substitute the
animated gifs for the static ones you will find in the data directory.
The difficult part is certainly to set up initial conditions so that the
elliptical orbit has a period that approximates the real one of the Moon
around the Earth. As an exercise for your students, delete the
initialConditions initialization page and ask your students to