Teaching ESL is difficult. Not only are you trying to teach them something but the communication channels may not be there, it adds another level of complexity. Also idioms and humour may not convert very well.

Keeping the attention of an entire class, while keeping if fun and disciplined is an interesting dynamic.

My punishments for bad behaviour while I was an ESL teacher were not violent (in Taiwan hitting a 5 year old kid with a metal ruler on the hands was normal)... I was far more evil. Kids can take pain, they are always playing and getting hurt. What they can't take with their youthful exuberance and short attention span is boredom. Standing in a corner or at the front of the class and having to be quiet while listening to the others play learning games curbs their naughty habits far quicker... very effective.

Also rewarding good behaviour and where possible just ignoring bad behaviour is useful. I tended only to really punish disruptive or rude behaviour. Cheating was brought up with the head of the school and the kids parents. They also would automatically score zero on their test.

And I found a lot of the 'bad' kids are bad because they are bored... and they turn out to be alot of the time some of the more intelligent ones... they just need more challenges and quicker feedback for their achievements.