More schools are banning cell phones. The academic benefits haven’t materialized

School cell phone bans aren’t as new as you might think. While a growing number of states have adopted them over the past three years, the practice dates to 1989, when Maryland prohibited the devices (and pagers) in an attempt to limit in-school communication among students who may have been involved in illegal activities. By 2009, in fact, nine out of 10 schools had banned cell phones. But that number began to drop as smartphones spread and parents wanted to be able to reach their kids in emergencies. Now that school phone bans are revving up again, questions are resurfacing about how effective they are at boosting test scores and reducing bullying. The early data suggest the results haven’t been as positive as many expected. A study from Stanford University’s Institute for Economic Policy Research and the National Bureau of Economic Research, released earlier this year, found virtually no impact on test scores in schools that have enforced bans for the past three years. That surprised the researchers, all of whom are college professors, says Jason Baron, a co-author of the study and assistant professor of economics at Duke University. “Our first reaction [when starting the study…