SAN MATEO, Calif. (KGO) -- Assistant Principal Adam Gelb's phone and email have been buzzing all week. From Illinois to Texas to Hawaii, he's been getting questions, feedback and congratulations from parents and educators for his new cellphone-free policy.
At the beginning of the school year, students at San Mateo High School each received a Yondr pouch. The San Francisco-based start-up, with a mission to create phone-free spaces, makes pouches that are locked magnetically. The phones stay with the owner, in the locked pouch.
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The Yondr pouches have been used at concerts and shows, but San Mateo High School is the largest public school in the country to use it for students. Each classroom has an unlocking device. Students put their phones into their pouch in the morning and it's unlocked by a teacher, at the end of the day.
We were there at the first day of school, when the policy took effect. Our story has been trending on our website and social media platforms. We paid a visit, one week later to get feedback.
Gelb showed us survey results from teachers who overwhelmingly say that student engagement is up with the new policy.
"One teacher stated that, some students feel less embarrassed when being silly, since no one is taking a picture or video of them. Another teacher said, I love seeing large groups of students talking to each other at lunch," Gelb said.
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"Students are getting better at their communication skills both with each other and their teachers."
At the district level, superintendent Kevin Skelly is looking at it closely, too, with an eye on wider implementation.
"This may be the most powerful social, emotional health thing that we do as a district, is to get kids off their phones," he said.
The new policy is resonating so much, he was randomly stopped by a stranger who saw his San Mateo High School lanyard.
"Someone I never knew came up to me and said I love this thing, I love what they're doing at San Mateo High School."
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Senior student Djelani Phillips-Diop was not sure about giving up his phone at first, but even he can't deny the difference.
"The highest screen time that I've ever noted was seven hours, yesterday I was at 30 minutes," he said.
Gelb say he's working on finessing gray areas - especially for students who may actually need their phones at all times. But he believes the method is working because it's an all-out ban.
"Now the average bathroom break is probably two-to-three minutes, whereas last year it was 20-30 minutes and we just had students wandering the halls with their head down on their phones."
Phillips-Diop says he even feels more creative, his sense is other students are more engaged, too.
"There's way more noise. People are singing, doing other fun stuff. Without phones now you gotta find some way to entertain yourself."
San Mateo High School setting trends with phone-free policy, fielding calls from across the country