I think a child of 3's far too young to be in a school environment, although a lot of scools here DO now accept younger ones for a couple of hours a day.
I believe that in Sweden, children start when they're 7, and by the time they reach 10, they're on a par with those whose children started before. I think this's one of the problems with today's society. Governments don't acknowledge the great job that most parents do, and force them to go out to work and put their children into childcare and schools. I think they should be paid a decent wage to stay at home if they want to, and teach their children through play, before they embark on formal education. the stress of trying to juggle a job, and a homelife, with time for the children, isn't working. There are now more folk taking sick leave through stress, than ever before, and it's the children who're losing out on having a parent there with them.