There comes a time in the life of all parents when their children turn into teenagers and soon after this cosmic event occurs, previously reasonable children begin begging to go to rock concerts. Most parents can tolerate anywhere from one to two years of teen-age harassment about this before they execute a time-honored parental move known as caving in.And so, with a prayer in their hearts and apocalypse on their minds, they watch as their beloved teen-ager rides off in a car driven by some marginally older kid and disappears into the night. The teenager's thrill of adventure is matched in every measure by the parents' conviction that they will never, ever see their child alive again. Rock concerts can make you lose your grip.

For Dee Karman, a mother of two who lives in Sterling Park, the rock concert ordeal began in June when her 14-year-old daughter Jill heard on the radio that Van Halen was coming to the Capital Centre at the end of July. "Who," responded Dee, "is he?"

"It' a group, not a he, " was the reply, doubtless one that was heard in a thousand different tones of exasperation around the Capital Beltway that day. Her daughter pleaded to go. But Dee Karman took an extraordinary step that crosses most parents' minds but one that is promptly driven out by anguished cries. "I said she could go, but two adults have to go with her," says Dee. "And she said, 'No, no, we can't have it that way,' and I said, 'It will be that way or you won't go.' She knew she didn't have any choice." Thus began one of Dee Karman's more traumatic adventures in motherhood.

Since her daughter was still in school, Dee was the one elected to get tickets and soon thereafter she found herself in line outside Hecht's at Tysons Corner. During the entire three-hour wait, she saw no one over 30. "I felt ancient," she recalled.

Shortly before last Wednesday, Dee found out that her husband, who works for the Federal Aviation Administration, was not going to be by her side for this one. He was going to be out of town. She considered selling the tickets. She tried to find another adult to go with her. She even tried to get a 20-year-old male neighbor to go with her. He could not. She was on her own, committed to shepherding four teen-age girls to safety through the unknown terrors of a Van Halen rock concert.

Shortly before Dee left her job as a dental receptionist that day, her daughter called her on the phone. "She said, 'I have your clothes laid out on the bed.' i got home and saw she had my oldest pair of jeans out, jeans I don't even wear outside the house, an old flannel shirt, and a scarf she wanted me to wear on my head. I said, 'No, way.' We've got to flatten your hair some way,'" Completing the ensemble was a new pair of shoes which Dee, to her daughter's chagrin, refused to wear outside for a while in order to get them dirty. "Here it is the end of July," says Dee, "and here I am in this flannel shirt. But she thought it was the only thing I had that looked awful enough.

"This is my little blond, blue-eyed daughter who wants to be a doctor. So here she is, dressed in the oldest clothes she owns. She has a scarf tied around her head like a sweatband, all of my Indian turquoise jewelry, the dangling earrings which I never let her wear, and all I could think of was, 'If your father saw you, he would never let you go out of the door.' She looked so bad, in fact, that I was afraid some of the neighbors might be outside and see us leave.

"I left my purse at home, so I stuffed everything in my pocket. I told them they couldn't go to the bathroom without me. I just didn't know what would go on if I wasn't in there. I pictured it would be really bad. . . . I was a nervous wreck going over there with them. I expected the worst."

But she ended up being surprised. She says the kids in the audience got their money's worth, and although she saw one girl who passed out, she came away with the impression that rock concert crowds aren't nearly as awful as they supposed to be. "In fact, several people bumped into me as we were walking and almost everyone said, 'Excuse me.' I thought it would really be a bad crowd. I found out i wasn't that way.

"I tried not to be too critical of the music. The thing that shocked me was the pot smoking. It was everywhere," she says.

Dee Karman said she scanned the audience at the sold-out concert and figured she was one of maybe five people over 30, which among other things, tells you how few parents would have done what she did when facing the decision of whether to allow a child to go to a rock concert. "Before I went, I would never have let her go alone. Now, I would feel easier about dropping her at the door and letting her go with a group of girls," she says.

"It's difficult," she mused in the quiet aftermath of her adventure. "As my mother said when I was growing up, "Wait until you have your own children and then you'll understand.'"