Smaller Is Better

Ask a parent or teacher to name the one thing that could improve student learning, and you're likely to hear about small classes. Ask a principal or superintendent the same question, and you'll probably get a different response. That's because many administrators play down the benefits of reducing the number of students in classrooms. Research, they say, has not conclusively shown that small classes are linked to improved student learning. Others point out that learning may improve but only when classes get down to 15 kids.

Well, not quite, say researchers from the Student/Teacher Achievement Ratio Project--Project STAR for short. As part of a two-phase study, they have been tracking classes of 15 to 17 students in 79 schools scattered across Tennessee since 1985. Their efforts make up the largest and longest-lasting experiment ever conducted on the effects of small classes on student achievement.

Not only do students in the early grades learn more in smaller classes, the project's investigators say, but they also continue to have an edge over the rest of their peers years after they return to normal-sized classrooms. What's more, the data they have collected are beginning to show that every time a student is added to a classroom, learning is diminished for the...