i will teach "History" the real one..

I think I would teach math. Math might be a subject where there is very little bias. It is what it is. Also, mathematics is fun.

Hi Sonnia, Cooking ;)

I'm already an English teacher, but one day I'd like to teach belly dancing.

Two possibilities: I would teach English to people who learn it as a second language. I did this once before when I volunteered for a short course at school in China and had a great time. The second choice is to teach mathematics - anywhere.