Schools across the country have invested billions of dollars in tablets, laptops, and high-speed internet with the expectation that more technology means better learning. But what does the research actually show?

A large body of evidence demonstrates that the issue is nuanced, with more downsides to technology use than most people expect.

Take, for example, an international study conducted by the Organization for Economic Co-operation and Development (OCED). In it, researchers examined standardized testing data from 15-year-olds across dozens of countries. They found that students who used technology the most in school tended to perform worse on assessments than those who used it moderately. Students in East Asian nations — where schools intentionally limit technology use and favor traditional instruction, particularly in math — consistently performed better on math assessments.

A similar assessment conducted by the Reboot Foundation, an educational organization based in France, analyzed data from across the globe. One data set was from the 2017 National Assessment of Educational Progress, a nationally-representative assessment of student knowledge in the U.S. It looked at Wisconsin fourth graders who used tablets frequently in classes and found the students scored about nine points lower than those who didn’t — a gap roughly equivalent to a full year of learning. In this study, the achievement gap between high- and low-technology users was largest among low-income students.

A separate analysis found that the more hours American students spent daily on computers doing English language arts, the lower their reading scores. The same analysis found that students in France who reported using the Internet every day for more than six hours in school scored 140 points lower on the Program for International Student Assessment’s reading assessment, which evaluates literacy in 15-year-olds, than students who reported no internet time.

The same holds true for younger children, too. A systematic review published in the journal Pediatric Research found that higher levels of screen time at ages two and three was significantly associated with poorer performance on developmental screening tests at ages 3 and 5.

But researchers say the evidence demonstrates that technology can also be used to promote learning. For example, the Reboot study found that using computers for research is associated with higher reading scores. And a meta-analysis of 36 studies published by Harvard researchers found there are literacy and math apps that do support learning.

How technology is used also matters. The OECD study found that nations with the best-performing students were more likely to use technology to connect and train teachers, instead of just putting devices in students’ hands. Schools that used technology to support teacher collaboration, professional development, and lesson-sharing saw better outcomes than those that focused primarily on student-facing devices.

“Like many topics related to technology and youth, the nuance matters,” said Amanda Purington, the director of ACT for Youth, a project at the Bronfenbrenner Center for Translational Research that supports healthy youth development. “It’s often more important how a technology is used than how much. And the role of adults matters. We can help young people learn how to use technology in ways that help rather than hinder them.”

What Parents and Educators Should Know

The evidence suggests that technology in the classroom can support or harm learning, depending on how it’s used. The evidence shows:

• More isn’t better. Students who use technology moderately tend to outperform both those who use it heavily and those who rarely use it.
• Younger children are especially vulnerable. Research on early screen exposure consistently shows that children who spend more time in front of screens have poorer developmental outcomes.
• The quality of educational apps varies. Parents and schools should look for programs based on educational research.
• The device doesn’t replace the teacher. Technology is most effective when it supports instruction. Teacher training and well-planned technology use make a big difference.

The take-home message: Using technology in educational settings is complex. To support student learning, the research shows moderate levels of technology use that supports broader educational goals works best.