When I taught through a shop they paid $50/student- Insurance 5-700/year, membership another 200. Hours per class, anywhere from 6-8 hours of classroom or more, poolwork another 8 hours on the short side, Open water training easy 4 hours each day (these are minimums, bare). So you got about 24 hours and that's not covering drive time, personal expenses, equipment, training tools and materials. Take a class of 8 students=$400 and then start subtracting expenses and divide by time, most instructors aren't making minimum wage--If you liked your instructor, buy 'em lunch, give a card, cash is nice, but I'll bet they'll be just as happy with a 'round of applause-'cause it's NOT about the Bejamins.