Class Size Reduction: Costly and Ineffective

Published April 1, 1999

With education a major public concern and the federal Elementary and Secondary Education Act (ESEA) up for reauthorization, many reforms are being put forward. Most of them reduce simply to “more of the same.” One of the most popular of these is class size reduction–the main effect of which will be a significant increase in the cost of education.

In California, for example, the initial mad scramble for teachers and space cost $1.5 billion when former Governor Pete Wilson mandated smaller classes in some grades. Last year, in mid-February, Peter Jennings reported on ABC-TV’s “World News Tonight” that 21,000 non-certified teachers were hired. He cited a school district that reduced its class size only to see student achievement fall.

While class size does make a difference, that difference depends on many variables, including grade level, types of students, subject matter, skills of the teacher, and teaching method.

A generation ago, sociologist James C. Coleman concluded that class size, by itself, is unimportant–a conclusion Senator Daniel P. Moynihan notes was consistent with findings over the previous 40 years. In fact, research by Harvard sociologist Christopher Jencks showed positive results with larger classes.

More recently, Jaime Escalante, a calculus teacher in Los Angeles, had remarkable success with disadvantaged students despite very large classes. Saying he wouldn’t turn away anyone, he often had up to 75 students per class.

Ironically, the argument that classes are too large has intensified as teacher-student ratios and average class sizes have fallen. From about 37 students per teacher in 1900, the average dropped to 27 in 1955, to 18 in 1986, to about 17 today.

When Eric Hanushek, chairman of the Economics Department at the University of Rochester, reviewed 152 studies of class size, he found only 14–less than 1 in 10–that reported significant relationships between class size and student achievement. About an equal number showed a negative relationship as showed a positive relationship, and the majority showed no significant relationship at all. A 1989 study at Johns Hopkins University concluded that results were minimal even when classes were reduced to as few as 15 students per class.

The cost of class-size reduction, on the other hand, is far from minimal. Michael Kirst has noted that California’s mandate for smaller classes cost an extra $800 per pupil per school year . . . not including the cost of new classroom space.

Over a decade ago, the Pennsylvania School Boards Association estimated that decreasing the average public school class by just one student nationwide would cost $6.5 billion. Given the increase in costs, such a move today might cost between $12 and $15 billion. Reducing classes from 25 students per class to 15 would require five teachers and five classrooms for every 75 students, compared to three of each now. That’s a cost increase of 67 percent, far in excess of achievement gains claimed by even the most optimistic study.

While the cost of arbitrary class-size reduction militates against its wholesale introduction, smaller classes do make a difference in some circumstances. Young, low-income, disadvantaged, and minority students in particular may benefit from careful targeting of such a reform.

President Bill Clinton, the principal advocate of arbitrary class-size reduction, has recently emphasized that we must stop investing in what doesn’t work and concentrate on what does. Continuing to press for mandated class-size reductions will waste billions of dollars on a reform that, to date, has produced minimal results at best. Far better to pursue more promising reforms that focus on genuine needs and more efficient options to improve student learning.

David Kirkpatrick is director of the School Choice Project at the Allegheny Institute, Pittsburgh, Pennsylvania, and Distinguished Fellow at the Blum Center, Marquette University, Milwaukee, Wisconsin. For more information, visit his Web site at