When I was a kid, I was lucky enough to go to a 2 month sleepaway camp one summer. Ever since, I've fantasized about a school that would be based on the same model:
Each kid met with her counsellor at the beginning of camp, and made goals for what she wanted to learn that year. Together, they came up with a schedule for the first week, and then they tweaked it the beginning of each subsequent week.
There were two "required" subjects - swimming and horseback riding. For those two, each kid was tested and placed into a group of kids at the same ability level. (Age had nothing to do with placement - it was all about what you could do in the test.) Each kid's lessons in the required subjects were scheduled for a particular time each day (so you might have 10:00 swimming and 3:00 riding). The rest of the day could be filled in however you liked, but during each activity period (each was about an hour long, and there were 6 in a day) you had to go SOMEWHERE. I think once kids were 12 they could roam a little more freely, but younger kids were not allowed to just drift.
However, the activities themselves were, for the most part, not actual "lessons" - you could go to the arts & craft shack from 9 - 10 and throw a pot, or you could go to the library and look up birds, or you could go to the archery range and take a test to get a badge, or on and on and on. Some activities required certain instruction before you could participate - you had to learn basic gun safety before you were allowed to try target shooting - but no one would "make" you take the instruction if you weren't interested.
At each activity, there was a counsellor. When you went to a station, you checked in with the counsellor, and told him/her what you wanted to work on during that activity period. S/he helped you get started, gave instruction if wanted/needed, and then helped you evaluate how you did. There were achievement levels at each activity - some of which were necessary to earn greater responsibility (like you had to prove you could canoe a mile in order to be allowed to canoe to the picnic island), and some of which were basically for "bragging rights" (hey! I got my intermediate level in sailing!). Some kids were motivated by the levels more than others. I only got three badges all summer, but some kids got 20-30! Even so, it was not really a competition - everyone was working to reach or exceed her OWN goals. I just happen to be a kid that doesn't care about badges, but I still learned tons of new things.
The camp also did a wonderful job of fostering a real sense of community. Every day at meals, a rotating group of kids were responsible for "waiting" tables and leading songs. And periodically the whole camp would come together for an activity, a play, or a game. Also, woven in the traditions of the camp were mentoring opportunities for the older kids. Each 12 - 14yo was assigned 2 or 3 junior campers, as a "big sister". The big sisters would help orient the new kids, ease homesick little ones, and generally keep tabs on their little sisters.
Oh I could go on and on (can ya tell??
) It was just such an ideal learning environment. I was a kinda timid kid, but I did things that summer that I never would have dreamed I could, because *I* was the one pushing me, instead of some grown-up!
When I was a kid, I used to daydream about a school where the main feature was everyone sat on cushions and there were no desks! 
