What parents wouldn't be tempted to lock up their preteens (“tweens”) until age 18? A study on adolescent perceptions of autonomy, however, finds that too much parental involvement is as problematic as too little. The research “highlights the difficult task that parents of early adolescents face,” says lead author Sara Goldstein, an assistant psychology professor at the University of New Orleans.

The researchers queried 785 adolescents three times over four years: in seventh grade, about their social autonomy and parental relationships; in eighth grade, about peer influences; and in 11th grade, about problem behaviors such as drinking and aggression. Kids given too much latitude, such as regularly staying at a friend's house after school with no adults present, were more likely to engage in riskier behaviors. But the same was true for kids whose parents were overly intrusive.

The goal, then, is balancing when to say no and when to let go, says co-author Pamela Davis-Kean, a developmental psychologist at the University of Michigan at Ann Arbor. For example, allow nights out but know who with and where. Or let tweens choose among supervised after-school activities. “It's important for parents to make adolescents feel like they do have some freedom,” says Goldstein, while still setting limits.