I have a 3 year old son who I'm looking into placing at another dayhome or preschool as well for 2-3 days a week in september and I totally understand what you're feeling. I keep on jumping from thoughts of "its so good for him and his development to experience someone, some place, and something different" which I truly do believe it is, but then i think oh my gosh, soon he's going to be in kindergarten and be gone half the day, and then its grade one and he's going to be gone altogether! So shouldn't I use this time to cherish each moment? And my thought then is, that yes, we should do both. And by going somewhere else to explore and learn, it is greatly benefiting him and at the same time makes me miss him so it makes our time more cherished and not taken for granted as much and it is still nice to get a break. He started out by doing a once a week 2hr class called "time for two's" which was unparented and he did two sessions of them starting this January(10 weeks each) and totally loved it! He asks to go to school sometimes over the weekend and every time he comes back from it he is so happy and excited and exhausted so I know its doing him good. When I see and hear this, I have no doubt that he is ready and should be in preschool or some sort of more guided class because it makes him happy and it definitely adds to his confidence and independence in being able to handle things on his own....such a valuable life skill that will keep on giving as he grows. So I say yes, put him in somehwere and definitely don't feel guilty about it. try to view it as more positive thing because it truly only does more good than bad.