"I feel there is more positivity and more things to laugh and joke about as we are more invested in our friendships."
Year 7 student Madi Clark said it was helping students make and keep friendships in their first year of junior high school.
"There are a lot of new girls. It's a good time to make friends and that's not so easy if you've got your head down in your device."
Year 7 Dean and languages teacher Neil Cheetham said instead of "obsessing over chats, internet content and social media posts", devices were merely being used for educational purposes and as an appropriate tool to enhance their learning.
Teachers had enjoyed seeing the students playing together at breaks, and the policy had led to more impromptu and imaginative games.
Research showed children with cellphones were more likely to get bullied or be the bullies, Cheetham said.
"So far this year there has been a distinct lack of issues to do with inappropriate online behaviour while the girls are at school.
"And with latest reports linking headphone and smartphone use to hearing loss, our 'no devices' policy is also benefiting long term student health."
Diocesan School for Girls joins others around the country that have made moves to lessen exposure to mobile devices during school hours.
St Joseph's Māori Girls' College in Napier hit the top 10 for University Entrance in 2018, and put its success down to a strict regime, including a cellphone ban.
Several Rotorua schools also introduced bans on cellphones, with principals and students also reporting increased productivity and better social interactions.