Are your grades hurting from playing with your Smartphone?

Are your grades hurting from playing with your Smartphone? (Cultura via Getty Images)

"We're pretty sure it's a causal effect, given that research," Junco says. "Five studies does not a concrete finding make, but it's pretty close."

Other researchers are wondering about the long-term effects of media multitasking. Does it merely distract us in the short term, Levine asks, or does it eventually transform us into more distractible people?

"I feel like you're missing something by not going into things in depth," Levine says. "My (relative), she says that since she started with 'the Facebook' and 'the this' and 'the that,' she can't read a whole novel anymore — she just can't get through that much."

Reiner, the Towson lecturer, says he's interested in the new developments in multitasking research, but when it comes to classroom policy, he's already made up his mind.

"I don't see that there's any way we can multitask and still think critically and deeply the way some of our classrooms and jobs require," he says.

Advice for parents

The best way to influence your child's media use in college is to start years earlier, when he or she gets that first cellphone, says pediatrician Michael Rich, director of the Center on Media and Child Health at Boston Children's Hospital.

Sit down with your child and have a real conversation about why she wants the cellphone and how she will use it, says Rich, who answers questions from the public about kids and media at Ask the Mediatrician ( Emphasize what the rules will be and what the consequences will be if the phone is used improperly. Establish from the beginning that the cellphone will be handed over to you at night for charging; this will eliminate late-night texting, which has been linked with sleep loss.

"Another very powerful tool that kids take over in their adolescence is the automobile, and we don't just hand them the keys to the car," Rich says. "We get them drivers' education, and we sit in the front seat with them, our knuckles white, and we move them gradually into their operation of this very useful, very freeing, but also very powerful and potentially very dangerous tool."