@jingstwat
Only the upper middle class can afford 150-200 and hour more than once per week anyway, and not all students are kids. Actually the higher the fee, the more likely the students are adults preparing for immigration or IELTS/TOEFL. If you want to play the class card, there are plenty of charitable groups who would love you to teach in small Yunnan town for room and board. I have friend who have done it and really enjoyed it.