More technology doesn’t guarantee more learning—and in some cases, it means less. That was the surprising finding of the Organization for Economic Cooperation and Development in its recently released “Students, Computers, and Learning” study, which looked at the impact of ed-tech across 65 countries and regional economies.

“Over the past 10 years, there has been no appreciable improvement in student achievement in reading, mathematics, or science, on average, in countries that have invested heavily in information and communication technologies for education,” the study’s authors write.

The study found that students who used computers extensively in school did far worse than students who used computers moderately, or rarely. The most positive news about computer use …