The London School of Economics did a comprehensive study of schools that were in the process of adopting a strict no-cell-phone policy. What they found was that banning cell phones led to a 6.4 percent across-the-board increase in test scores. However, the lower-achieving students had the greatest increase, averaging a 14 percent improvement. By removing the screens that were separating the students from their teachers, these schools turned F students into C students.
