Ok here's one not mentioned. I bought two Yamaha Sno Scoots for my 6 & 8 year olds. They love them. Their light, manuverable, can go about 35 mph and run all day without using much gas. This worked out great, my 8 year old daughter weighed 68 lbs when she started riding their scoots ( after they shared a kitty cat ) no problem handling it. It's been two years now and we are just starting to plan the transition to a 340 / 440. It will either be next year or the year after. She still only weighs 72 lbs. Good luck lots of choices out there.