I know that my advise is going to be contrary to almost everyone else who has responded so far, but since your asking people's opinions, here is mine: I think that around 3 is a good time to start preschool, even if its just on a part-time basis. There is a lot to be said for letting him just be little and he's got lots of school ahead of him and all that, but that being said, going from stay at home kiddo to kindergarten with out anything to prepare him ahead of time is a huge, huge adjustment. He's going to go from doing whatever he wants whenever he wants (with your approval of course) to having to follow a teacher's stricter schedule. In addition, he's going to have homework, have to listen to and work with several different teachers (p.e., music, k-teacher, etc). Going from preschool to kindergarten is a big change as it is (my son did that last year), but from home to kindergarten is bigger. Also, kids are information sponges at this age, so letting him go somepleace where the teachers can help him prepare for everything they are expected to know in kindergarten can only help him. While yes, kindergarten kids all do start at different levels and end up roughly the same place, but why make him start from the lowest level and have to work harder to get there, when you can give him a little head start. Now I am not suggesting breaking the bank to do this, of course, but if you can find a good part time place that you can afford, I think your child's educational success is one of the most important things you can invest in. I can recommend two places to check out, depending on where you live: in chandler Sunny Days Learning Center, the director is Cindy and she's very nice. In QC Shining Stars Learning Center, director Vickie, also very nice. Kyrene schools districts program also is wonderful, but it can have waiting lists, so if you are interested in that you should check it out soon. Good luck!