I think a lot of it depends on your definition of "date". Many of you say that you won't allow dating until your son or daughter is 15/16. My youngest daughter is 14 and when she was in middle school it seemed like everyone was "going out" with someone. Usually the couple didn't last very long, and they never really went "out" anywhere. There was a lot of talking on IM and phones, maybe a group of boys and girls going to the movies, and the school dances were probably the highlight of their social lives.
My daughter went "out" with a boy from the middle of seventh grade until the end of eighth grade, (about 16 months), an eternity for middle schoolers. Looking back on it now, I can't believe they were only 121/2 and 13 when they first became a couple.
Now before I get flamed, I want to say that it was a VERY controlled situation. For a long time, they only talked on the phone, (infrequently), talked on IM, and attended a few school dances, (not really as a couple, but with friends). The first few times they went to a movie together, either my husband and I or the boy's mom or dad, also went and sat in the same theatre.
They really never went anywhere by themselves. They usually spent time at each other's houses, again ALWAYS with adult supervision nearby. We ALWAYS called his parents and they would always call us before the two got together. Both sets of parents knew the rules, (NEVER allow them to be without adults nearby, no going into bedrooms, etc.). We maintained communication throughout their relationship.
Both kids were involved in other activities, (football for him, dance for her), and they spent time with a lot of friends. They did things with both families and were each other's best friend. Now don't think we were always comfortable with them being so involved with each other. I was always second guessing everything. Are they spending too much time with each other? If we limit their time together, will that just make them want to spend MORE time together?
In summary, I really think the dating issue isn't so much an age thing, but more of an individual situation. Young teens need A LOT of parental involvement. Communication MUST be open between teen and parent and between the parents of both kids. And, again, much depends on the kids themselves. I have a son who is 23, and never really was interested in dating until well into his teens, (late high school), and a daughter, 20, who didn't have a boyfriend, (she had tons of friends who were girls AND boys), until the beginning of Sophomore year).
Sorry for this being so long, but I really think it's hard to pinpoint one exact age to "date", and again, the word "date" can mean different things to different people.