DS1 (3.5 y/o, barely 3 when he started) has THRIVED in preschool for this very reason. When he started, he would NOT color or draw. Because he wasn't good at it (poor kid has my ability, or lack of ability, when it comes to drawing), he would just ask us to draw things for him. Going to preschool, and being with a bunch of kids his age and older, and seeing them drawing things that are... not always recognizable, has turned him into an art fiend. He's still probably near the bottom of the pile when it comes to artistic renderings at school, but he ENJOYS it. He draws and cuts and glues and any manner of fun things.
Preschool, then, for us (YMMV), actually helped us deal with his asynchronous nature. Yes, he's reading and adding and subtracting and that's all mind-blowing and awesome (though I don't think his teachers really know what he can do and DS1 is not a show-offer these days... and in some ways I'm not inclined to tell them), but he's also having to explore stuff that he wouldn't touch at home because it wasn't his "thing."
Yeah, he does his "best" work when it's stuff he's good at, and I think that's human nature, but it has been nice to see him expand his horizons beyond what he's good at. Mixed-age is good for us right now. I'm not sure how this will go next year when he's one of the older kids, as he's already kind of maxing out their "academic" stuff, but we'll cross that bridge when we come to it.
