I used to worry about the same thing. Both my husband and I were public schooled and there is nothing we miss about it. We both wanted something wonderful for our children. I was bored to tears in public school.
I tried public school with my older two and although we live in a very christian area I was so not impressed. My daughter was bored and would come home in tears. By the end of the year she hated learning and school. I want my children to love learning. Since homeschooling, my daughter has become excited about life. She has been on more fieldtrips than her public schooled peers and has had more fun. She went back to third grade when we moved and in that year we saw her love of learning die as well as her interest and also saw that no matter how hard she tried in PE it wasn't enough for her teacher. She would have been a straight A student otherwise, mind you a totally bored one. By the end of the school year she was making up her own work to turn in and asking me to give her home school work because she was so bored.
There are so many oppurtunities, group outings, fieldtrips, proms for homeschool children. The most amazing thing I've noticed though is that older children and younger children interact well with each other. Homeschooled children at least the ones I know can have intelligent conversations with adults. I've tried talking to my children's public schooled friend's and it's not the same. It's like they don't know how to have a conversation with an adult. I love how well homeschooled children get along with each other and work things out and use their imagination. My kids always make a new friend when we have group get togethers. That didn't happen in public school. There is a pecking order.
Another thing that is intersting to me is that I'm finding more and more teachers that are homeschooling. When I ask them why they tell me it's because they see what goes on in the schools and the time that is wasted on silly things like the furndraisers (I don't plan on my child becomming a door to door salesperson anyway) and that they want something better for their own children. For $20 a year you can have a membership to an educational website that is the same one public school teacher's use.
So far the only thing my homeschooled children have missed out on are: sexual harrashment, bullies, learning foul language and to be afraid, learning to lie, icky school lunches, sitting in hard chairs for most of the day. Having very limited outside play and PE only once a week, being made fun of because they don't have as much money as the "Jones". So far there is nothing in that list that I'm regretting my kids missed out on.
My kids learn more, have more fun, go on more fieldtrips(school activities), meet new people, They don't have to worry about someone showing up with a weapon, being "locked in" for their safety etc.
My children deserve the best. That is why we have choosen to homeschool them. So that they can have more opportunities. What is so wonderful about sitting in a square building most of the day. So what if they don't all sit down, walk a straight line or act like a bunch of good little trained Seals (someone mentioned that the homeschoolers she saw didn't know how to line up-of course not since their parent's weren't dealing with 30 kids at a time).
All my children are individuals and they deserve individual attention and respect. Not all children desire to be cheerleaders and jocks.
So unless you are going to lock your child in a closet and not be involved with other groups or homeschoolers than your children are going to get plenty of socialization at least with homeschooling you have a fighting chance at weeding out the bad stuff. There is nothing wrong with parents wanting to be there for their children and to teach them.
It seems that more and more society is trying to get children away from their families, put them in public schools longer and at younger ages. Than they wonder why the stress rate, suicide rate etc is going up in schools.