Group dating isn't new, but it might be more familiar to teens' grandparents or great-grandparents than their parents, notes Dr. Jeff Lindenbaum, director of teen health services for Group Health Cooperative.

"It's sort of a U-shaped trend of only group dating, then more individual and now back to group," he said.

From a teen's perspective, group activities appeal in several ways, he said.

• It's a way to avoid having to be emotionally ready for a committed relationship. "They delay individual dating until they're ready to benefit from a one-on-one relationship," he said.

• They're not locked into dating only one person. "If you're interested in Person A today and Person B tomorrow, you don't have to cut off contact with Person A," he explained.

• It's cheaper, because when you go out in a group there's no obligation to pay for a date.

• Depending on the group, it may be easier to avoid pressures for sexual contact. "Teens are sexually mature before they're emotionally mature," he said. "This buys some time to let emotional maturity catch up."

Teens also report group outings are less awkward than having to ask someone out and suffer through the uncomfortable silences of a first date, Lindenbaum said. Plus, some say parents are more lenient about group dates in terms of curfew.

However, parents shouldn't assume all groups are safer than one-on-one dates, Lindenbaum said. "It depends on the group norm," he said. And where they're going: "If it's a big party, they can still go off into separate rooms."

Even if teens don't have a regular boyfriend/girlfriend, the phenomenon of casual pairings through "friends with benefits" or one-time "hookups" is found at the high-school level, Lindenbaum said. As he notes, "The big difference is for parents, 'free love' occurred in college and beyond."