Seeing our youngest son, Adam, play alone on the playground every day was very hard on me. As a teacher, I have seen him interact with classmates and realize that he is very immature. However, my husband and I have learned that he is just like the little tiger in the children's book, Leo the Late Bloomer. He'll be just fine, but we need to help him along the way.
My husband and I felt something needed to be done about Adam's lack of friends, but we didn't quite know what to do, so we tried providing more social opportunities for him and it has worked very well. We've made it a point to let him invite friends over often. I've made sure that I watched how he interacted with these other kids and corrected him privately when I thought that he was being selfish or mean. We also did away with our rule of 'no friends on weekdays' that we'd established with our older son that had friends popping by all the time. Adam has really come a long way since we did that, and it is a joy to see him happily playing with other boys on the playground and chatting with friends in the cafeteria. Many other families are very busy, as ours is, so often times we have to make the effort to invite Adam's friends over. Since there are no other children his age, in our neighborhood, his friends don't just pop by. We'll often go miles to pick up friends or take them home.
My advice to any parent that has a child with poor social skills is to just help the child by doing whatever it takes; involving him/her in sports, having friends over, letting him/her go to others' homes or parties, listening carefully to the child, role-playing, trying to figure out what he or she may be saying or doing that turns kids off, even signing the child up for a Big Brother/Big Sister program. Big Brothers/Big Sisters has a school program in which students sixteen years of age or older can spend time with younger students during special activities, lunch, and recess times. The 'Bigs' are screened thoroughly and can be excellent role models.
We've discovered that having an elementary school child with poor social skills is not a disaster. There are many things parents can do to help their children develop those skills. Elementary years are the formative years in which kids are developing. Some are better with their social skills than others, but we're all better at something than someone else. Mastering the art establishing good social relationships is so tough that many teens and adults are still working on it. That's why books like, How to Win Friends and Influence People are written.