Here is a little tip to clean the fingerprints off your walls ...
It's greasy, and it's normal, but if it's greasy it's hard to clean properly, is it not? The trick is quite simple, and your teacher could have provided you with the required material back in the day if only she had known!
Pencil the area in question of your wall with a simple white chalk. Do not get me wrong - the idea here is not to take fingerprints! Technically, the chalk will absorb the fat left by the fingers; then, just pass a cloth to remove the chalk, and you're done!