Instead of rotan, use the following.

a) belt
b) whip
c) push ups or any other physical exercise.

ban rotan. just ask them to STAND behind/outside the class AND STRIP and hold their heavy bags over their head

no touching, less insulting and receive some free physical training
if everything also ban might as well send their children to cc and let they build their confidence while sohaing and hamkachaning other people while playing dota