Try going on things like AsiaXpat for the various metropoli (more info in the Links board!) and looking at the summer camp ads there....they've been popping up there for a while now. That would give you a broad spectrum of ads to which you can compare your school's camp.
Some of these things pay pretty well. You may find 5K to be on the low end.
Of course, I ALWAYS think salaries are on the low end.