I have a 5 1/2 year old boy who bikes A LOT - first time I took him on a real bike ride we went about 5 miles. We bike 5-7 miles on average a few times a week and will do more this summer. However, he needs a new bike and i'm thinking one w/a few gears would be appropriate based on his ability and he'll pick it up easily i think. I have no idea what types of bikes to look at. Ideally no more than around $250 tops and something that can last for 3 yrs or so. I've tried looking at buying guides but for his age they're all geared towards the 'learning to ride" side of things which we've definitely got down pat.