When I used to teach quilting classes, I would charge $10 per hour per student. I would cancel the class if I did not have at least 6. So a 3 hour class would be $30. Of that, the shop kept half, and gave the students a 20% discount on supplies for the class. Some instructors took as many people as they could squeeze into the room and charge a little less, but I limited my classes to 6-10 persons.
So I would earn $30-60 per hour of class time. It might seem a bit high, but class time does not include all the time and expense I had in prepping for the class. Besides a step by step lesson plan, I would make several samples of the finished quilts in different colorways and sizes, plus make samples of each step with notes and measurements printed on them that could be passed around and examined. Also, because I kept the class size small, I was able to give personalized attention to anyone having trouble.