we've been only doing 3hrs/day public preschool since November with DS4.5 and he loved it as long as he was sick all the time and missing out half the days but now that the winter's ending and he's not as sick anymore (only missed 2 days in the last 3 weeks) he's been acting out, getting bored, telling the teacher he doesn't need to be there because he knows the stuff. Really, the only reason why he goes to school is to "see his friends". We keep homeschooling as a back up but for now we are ready to sign him up for K and see how things go. It's only 3hrs/day K so he might do fine. But if things get tough, we will pull him out.