With the shift to computerized testing, tablets in the classroom and digitized personal records, schools are collecting more data than ever on how children are doing.

Now, some educators believe, it's time to put that data to use.

Every answer on a quiz can be analyzed to give teachers a precise picture of what their students have learned. A pattern of wrong answers is no longer just a bad grade; teachers can get clues to why students picked the wrong answer. Publishers can analyze which chapters in their textbooks are working, and which might need revising.

Steven Ross, a professor at the Center for Research and Reform in Education at Johns Hopkins University, says using data to help tailor education to individuals will drive learning in the future. "Most of us in research and education policy think that for today's and tomorrow's generation of kids, it's probably the only way," he says.

Perhaps the biggest stumbling block to using data in schools isn't technological, though. Rather, it's the fear that doing so will invade the privacy of students. Parents worry, for example, that details of a child's early struggles with reading could hurt them with future employers—or with schoolyard bullies.