Question: What temptation is hardest for teenagers to resist?

Answer: Cell phones

How do I know? I’ve been studying self-control in adolescence for nearly two decades, and increasingly, my data implicate cell phones as the single most potent temptation in the lives of young people.

Phones are a limitless source of immediate gratification. Finished scrolling through your Instagram feed? You can rewatch an episode of The Office. Craving something else? There’s always Snapchat, TikTok, and…the list goes on.

When pitted against homework and studying, phones are the “easy” choice because, to paraphrase Aristotle, the fruits of education are sweet but the roots are often bitter. In other words, thinking hard about things you don’t yet understand is not nearly as effortlessly pleasurable as the myriad diversions you have in the palm of your hand.

It’s impractical to ask teenagers to swear off phones altogether. But it is possible to share evidence-based strategies for outsmarting their smartphones. The trick I like best is also the one most commonly recommended by undergraduates in the classes I’m teaching this year — what scientists call situation modification. It involves intentionally changing your physical surroundings to make it easier to resist temptation.

Consider, for example, this data collected from thousands of high school students on Character Lab Research Network. The farther students reported keeping their phones when trying to study, the higher their report card grades (see the illustration).

Of course, correlation is not causation. Still, my guess is that the young people in your life have already discovered that their phone is less tempting when it’s out of sight, out of earshot, and hard to reach. But it may not have occurred to them that they can, as a habit, capitalize on situation modification.

For the middle or high school students in your life, here are suggestions, courtesy of my undergraduates, on how to successfully resist reaching for their phone:

Try: ...putting your phone in a closet or on another floor … downloading the SelfControl app, which blacklists access to websites for a predetermined time period … putting the notifications on your computer on “do not disturb” and shutting off your phone for 30 minutes at a time … turning your phone completely off and putting it in a random bag somewhere (this will especially help when you have a busy day with lots of plans already set out) … plugging your phone in across the room before getting in bed so you go to sleep without wasting time on your phone.

Angela Duckworth is the founder and CEO of Character Lab and a psychology professor at the University of Pennsylvania. You can sign up to receive her Tip of the Week — actionable advice about the science of character — at characterlab.org.