Parenting Tips for Your Preschooler - Parent Cooperatives and HeadStart Programs
I've never heard of a professional actually recommending that a child be sent to preschool, not these days anyway. The most I've heard is that it couldn't hurt. School of any kind is the place where children begin to learn social skills. Child development play teaches kids how to interact, share, and think of others. The best example I know of is the Headstart Program, which is a preschool setting for low income children age's three to five.
But must you send your child to preschool? There are as many valid reasons for not doing so as there are arguments for. A new baby in the house could cause the older child to feel left out if they are being sent to preschool every day, but personally I think it is a great break for the mom (just being honest) and a wonderful way to help the older child feel a little "grown up" if you handle it correctly. This is called parenting with love and logic.
If you want to keep them home, that's great, too. They are your children. Don't let anyone else's opinion sway you if you are set on keeping them home for another year. The logic in this attitude is that children are often pushed to grow up too fast, and one of those ways is sending them to school too early. If they have separation anxiety (not the first day of school jitters, real separation anxiety) then by all means keep them home-why traumatize them? You can invite other kids of the same age over and they will still learn social skills. You can learn about child development and nutrition and have a play day, serving little snacks and teaching them yourself. In fact, take turns with other parents once a week and you've got yourself a co-op.
Now if your child is in dire need of learning some social skills, there is no better teacher than a peer group, believe me. A kid who is a little high strung at home will settle down tremendously after learning in a public setting that his behavior will not be tolerated by his peers. A child who seems to get bored easily at home might enjoy the structured curriculum of a preschool setting. It is a fact that child development play is better expressed through interaction with other children before interaction with only adults-easier to gauge, too.