We have camped with different families of people we hang out with at home and it wasn't a good match camping 3 out of 4 times.....
We usually meet people at the site, and my kids are usually the ones that do the seeking (They are very social through sports).
I like it that way because taking people with you, I felt the obligation to hang with them. When you meet strangers, if it isn't a good match, you just stick to your campsite....
BTW, i am 43 and have kids your age...LOL. So much for being young...