It starts out innocently enough: a seventh-grader and a few friends sneak into an R-rated movie without paying, or that girl he had a crush on is now suddenly a “girlfriend” he made out with in an empty hallway, or a tween slips out of class to spend the afternoon in a Starbucks instead.

Normal pre-teen shenanigans, right?

Not so, says University of Virginia Psychology Professor Joseph Allen, whose study on the long-term consequences of being “cool” when you’re perhaps a little too young, was published in the journal Child Development.

“They look like they’re on the fast track to adulthood, but it ends up being a dead end,” Allen said in an interview.

According to the study, which surveyed 184 seventh- and eighth-graders and then followed up with them 10 years later, the kids who were involved in minor delinquent behaviors or precocious romance and obsessed with physical appearance and social status were much worse off in adulthood than their less “cool” friends.

In Allen’s data, he found that at 22 or 23 years old, these kids had 45 percent higher rates of alcohol and drug problems and 22 percent higher rates of criminal behavior; their ratings of social competency — their ability to have normal and positive relationships with others — were 24 percent lower than their peers.

“We were surprised by it, because in general, being popular and being accepted by your peers is associated with good outcomes,” Allen said. “There’s a subgroup that kind of cheats — they’re trying to appear more mature than they are.

“These are behaviors that a lot of parents would think are typical adolescent behaviors but early on are really marker of significant risk,” he added.

The study wasn’t looking at kids who were chronic troublemakers or had already regularly encountered the criminal justice system in middle school. But it surveyed a subset of tween and early-teen children who Allen calls the “social strivers.”

These children tend to seek out attractive friend groups — “Mean Girls” style — and are in relationships at a young age, but might not actually be having sex. They flout rules and even break minor laws like shoplifting, but aren’t committing serious crimes.

Most of all, they are considered very socially adept at a young age. But then that advantage wears off, Allen said.

In high school, their social striving might take them to alcohol and drugs; as they become adults, they fall behind their peers socially.

“It’s not that they’re regressing, but they’re not advancing,” Allen said. “Behaviors that seem cool for a 13-year-old to engage in don’t seem quite as cool when you’re in high school.

“They hit on this strategy and they stick to it.”

So for parents, the study could be terrifying, though Allen says it needn’t be.

If kids get off the “cool” track, they won’t necessarily encounter the same problems as the children in this study.

And for parents of children who worry when their child isn’t doing the things they expect normal teens and pre-teens to do, they might want to cut their kids a little slack.

“A lot of parents think, ‘Well, my kid seems a little slow,'” Allen said. “That’s not only fine, but it’s good.”

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