Another song that works very well as music for ballet class is “Be our Guest” (Ashman/Merkin), from Beauty and the Beast. It can be transformed to have several uses, all assisted by the pronounced anacrusis, or pick up (the “Be our” portion of “Be our Guest”)
At a slower tempo, using a dotted rhythm on the anacrusis, it makes a perfect piece for an accent-in grands battements exercise. At a quicker tempo, with a lighter touch, it works well for fouettes. Some ballet instructors like to use marches for pirouettes; this piece can fit the bill perfectly.
If you really want to get creative, you can change the meter to 3/4, and transform it into a grand allegro waltz.
There may be other uses, but all in all, this is a very handy song for ballet pianists.