I am a firm believer that 12 - 15 year olds can rotary cut and 6 is not a huge number to manage. That being said - I agree that the first project ought to be "pre-cut" kit type of project if it is only a one lesson sort of thing. They will want to feel as if they accomplished something and will want to go home with something in their hand. We recently did Pillowcases with 12 Girl Scouts and the pillow cases were all pre-cut and ready to go. They did great and all went home with pillow cases.