He’s a little older than most of the students, but Gov. Ned Lamont was up bright and early for the first day of school at Berlin High School on Thursday.

Lamont is pushing other districts to follow Berlin’s lead and ban cell phones in class. But parents, concerned about reaching their kids in an emergency, are divided about the idea.

As phones and social media has become ubiquitous, so have distractions in the classroom.

“It is preserving the learning environment,” said the state’s Education Commissioner Charlene Russell-Tucker. “Making sure that the educator isn’t constantly saying, ‘Put your phones away,’ so they can focus on learning.”

This year, students in Berlin must lock up their mobile devices in cases when they arrive at school.

“They have cellphone towers,” Lamont said. “The kids leave their cell phones in the tower, go into the classroom, focus and study.”

Last week, the State Department of Education issued new guidance on phones in the classroom.

It recommends that elementary and middle schools collect mobile devices at the beginning of the day. High schoolers could keep their phones, but must turn them off in class.

Across Connecticut, dozens of districts already restrict phones in class. Many keep them sealed in Yondr pouches that are seen at concerts.

Some parents love the idea.

“Kids need to learn, and the only way you learn is by being observant and paying attention,” said parent Candace King. But what if there's an emergency? School leaders say, calling your kids directly isn’t the best approach. “I know all the schools, they say, ‘Parents, here’s the emergency number,” Lamont said. “Call this. We can tell you exactly what’s going on and how we’re handling it.”

But some parents would want to keep a direct line to their kids.

“In the heat of the moment, that’s a tough one,” said Terry Parese, of Easton. “If you’ve got all these parents trying to call the school. I mean, I don’t know of that's something that would work.”

The new state guidelines are only recommendations.

School districts are free to keep phones in the classroom if they want to.