In praise of classroom cell phone bans

In praise of classroom cell phone bans
© iStock

Always a science-fiction technophile, in the last century I dreamed of future technologies that would turn my lecture classes into interactive exchanges between student and instructor. In this century the technologies arrived in the form of online course platforms and personal response systems for the classroom.

In 2005 I adopted both technologies and replaced broadcast lecturing with a more Socratic method, called distributed questioning, as my principal instructional methodology. It was known from laboratory experiments that when someone answers a question about study materials, they are likely to remember the question and their answer a long time. They are even likely to remember the correct answer if told it later as feedback.

For six years, as I became more skilled at using distributed questioning as an instructional methodology, exam performance in my class improved. Performance on the final exam increased from 73 percent correct in 2005 to 90 percent correct in 2010.


I was close to attaining my goal that 90 percent of my class would attain 90 percent correct on the final exam and they would all get As. But then exam performance declined dramatically. In 2012 the average score on the final exam was 80 percent, and it remained there through 2014. What had impaired the academic performance of my students? I only had to look out at them to see the likely answer.

I am old enough that when I grew up there was a universal social convention that you looked someone in the eyes when you spoke to them or they spoke to you. This convention extended to audiences in classrooms and theaters. Of course there was an occasional transgression. I can remember a high school math teacher removing an open newspaper from my lap during math class that I had been looking at while he spoke. But I knew that I had done something wrong and I rarely did it again. The opportunities for divided attention in the classroom were limited and of limited appeal.

Technology does not create new behaviors, but it can unexpectedly exacerbate a bad one. When I looked out at my students in 2014 it was obvious that most of them were no longer in class, except for their physical presence. Their attention was primarily on the laptop/tablet/cell phone on their desk. They acknowledged my presence with a clicker press when asked, but they were no longer engaged.

I have the advantage of teaching two large lecture sections back-to-back, twice a week. I performed an experiment in which a proctor insured that no electronic devices were opened for one section on Tuesday and for the other section on Thursday. For the alternate classes the students could do what they pleased but I collected self-report data on device use.

The result was that divided attention during class impaired subsequent exam performance. For material presented when students were not allowed to divide attention, final exam correct performance was 87 percent versus 80 percent when they were allowed to do as they pleased.


Furthermore, students took review quizzes and unit exams before the final exam that gave them multiple opportunities to learn the material taught in class. In most classes, in which there is not systematic repeated re-instruction and re-testing of study materials, the decline in final exam performance would be greater.

Since then I have not permitted students to divide attention in my class because of its substantial effect on academic performance. I think that such a policy should be revived as a universal social norm. There are some efforts in this direction. Other researchers, educators and health professionals have noticed the unintended, sometimes deleterious effects of cell phones and social media on child development. There is an organization, Children and Screens, that promotes research into new technologies and awareness of its effects. Edward MarkeyEdward (Ed) John MarkeyThe Hill's Campaign Report: Biden's latest plan on racial inequality The Boston Globe endorses Markey in primary against Kennedy OVERNIGHT ENERGY: EPA effort to boost uranium mining leaves green groups worried about water | DNC climate platform draft calls for net-zero emissions by 2050 | Duckworth introduces safety net bill for coal country MORE (D-Mass.) has taken an interest in its findings.

In some parts of the world, classroom cellphone bans are in effect. In September 2018, the French government banned mobile phones from schools for students from preschool through age 15.

A British study published in 2015 compared secondary students’ standardized test scores before and after the adoption of cell phone bans. Ninety-one schools participated, from four of the country’s largest cities. None of the schools had phone bans in place when the study started in 2012. By the end, all but one did. The authors found that if a school banned cell phones and got its students to comply, then student test scores improved. The biggest driver of this effect was improvement by the schools’ most underachieving students.

But there are strong countervailing forces against the re-establishment of a norm of a student giving undivided attention to a teacher in the United States. It is not known how many school districts have instituted cell phone policies because a thorough national survey has not been done and announcing a policy is different from enforcing it. In 2010, Pew reported that almost 80 percent of kids were texting in the classroom — even 58 percent in classrooms where phones were banned.

No government or private agency offers funds for experimental investigations of the effects of technology on human cognition or social behavior so there is only anecdotal evidence of what may be epochal changes in child development, learning and knowledge. Rather, the largely unacknowledged effect of cell phone use on live instruction allows policymakers to move in an attractive direction: replacing costly live instruction with much less expensive online instruction.

Beginning at the collegiate level and now increasingly at the high school level, there is an effort to entice students away from live to online instruction. Laboratory research has consistently shown that any kind of recorded, hence non-interactive and non-social, instruction is inferior to live instruction.

Until now, it has been easy to ignore this fact because there is no funding available for experiments that compare the effects of online versus live instruction on exam performance. In the future, as funding for live instruction dwindles and the shift to online instruction becomes more coercive, there may be pushback.

To justify the shift to online instruction, there may finally be an incentive to fund a well-controlled experimental study comparing online versus live instruction. But by this time classroom instruction may be so degraded by the unchecked divided attention of the students that it no longer produces better exam performance. Thus the degradation of classroom instruction through unchecked divided attention will be the first step in (and justification for) eliminating live instruction altogether for non-wealthy students.

Arnold Glass is a professor of psychology at Rutgers University. He is the author of Cognition: A Neuroscience Approach published by Cambridge University Press