Before class each day, a high-school teacher in Indianapolis grabs a clear plastic bag and fastens it to her waist with a ribbon. The homemade pouch is a repository for phones that are either confiscated or handed over voluntarily by students who don’t want to be tempted to tap or swipe during class.

She calls it the “phoney pack,” and the magic of the makeshift vault isn’t that it keeps devices out of reach. It’s that it lowers students’ anxiety by keeping their phones in view.

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