Newburgh, New York — At Newburgh Free Academy in New York, cell phones are locked away for the entire school day, including lunch.

Students like Tyson Hill and Monique May say it is a relief after constantly being on their phones during the COVID-19 lockdown, when screen time among adolescents more than doubled, according to a study last year in the Journal of the American Medical Association Pediatrics.

"I blame my darkest moments because of my phone," Tyson told CBS News.

May said phone and social media use during this time was entirely to blame for her mental health struggles.

"All of it, for me personally," May said.

According to the U.S. Centers for Disease Control and Prevention, 57% of high school girls in the U.S. felt persistently sad or hopeless during the pandemic, double that of boys.

May disclosed she sometimes felt bullied or isolated after looking at social media.

"Throughout my middle school experience, like there was a lot of people talking about you, whether it be on Snapchat, posting a story that made fun of the way you looked," May said. "It made me feel depressed."

In May, U.S. Surgeon General Dr. Vivek Murthy issued an advisory on the effects of social media on youth mental health.

"The youth mental health crisis is the defining public health issue of our time," Murthy told CBS News. "If we do not address it with urgency, then I worry we will lose an entire generation of children to depression, anxiety and suicide."

Murthy said he would consider calling for "restrictions" on the use of smartphones during school hours.

"I do think that we should have restrictions on phones in the school setting," Murthy explained. "We fundamentally have to understand that these devices, and in particular social media, is behaving largely as addictive element."

Ebony Clark, assistant principal at Newburgh Free Academy, says banning phones has helped cut down on online bullying.

"All I'm doing is giving them the opportunity to engage in school and leave the drama outside these doors," Clark said.

May said she's experienced improvements in her mental health because of Newburgh's phone restrictions.

"I'm more confident in who I am," May said. "And I think that just comes from not being able to worry about what other people are saying about me. Just being me."

In:
• Cellphones
• Social Media
• Mental Health
• Bullying