Schools that banned cell phones saw higher student test performance, a study released this week found.

The study’s authors surveyed 91 schools in four English cities before and after cellphone bans were implemented.

They found student test scores rose after the bans, with low-achieving, special education and low-income students benefiting the most. After the ban, students were 2 percentage points more likely to pass high-school exit exams, according to the researchers.

The authors — economists at Louisiana State University and the University of Texas at Austin — suggest restricting mobile phone use could be a “low-cost policy to reduce educational inequalities.”

But some schools in Georgia and nationally are actually encouraging students to bring cell phones, tablets and other devices to school under "Bring Your Own Device" policies so students can use them during class and for school projects.

And a recent national survey found that high school students are more likely to use their own digital devices than school-provided ones.

Under current Atlanta Public Schools policy, cell phones must be "out of sight and turned off during the official school day and the lunch break except in cases of health or other unusual reasons" though students "may be permitted to turn on and use personal devices during the school day" for instructional purposes.