View all Articles
Commentary By Jay P. Greene

Smaller Classes Mean Less-Qualified Teachers

Economics, Education, Cities Finance, Pre K-12

A recent international study, which found that Canadian students do quite well despite relatively large classes, has Canadians rethinking the merits of class-size reduction as an education strategy. Asking parents whether they want smaller class sizes for their children is like asking them whether they want to have a personal chef -- everyone imagines he’ll get Emeril shouting “bam!” right in his own kitchen. But there aren’t enough really great chefs to hire one for everybody. Once you’ve hired Emeril, Julia Child, and all four of the Iron Chefs, you have to start lowering your standards. So if every single Canadian were to get his own personal chef, instead of Emeril you’d be more likely to get a teenage fry cook from a fast food joint.

The same is true for class size reduction. To dramatically reduce class sizes, Canada would have to hire many new teachers; to fill all those new teaching positions, it would have to dip deeper into the labour pool. Thus the person standing in front of your child’s smaller class would probably be significantly less qualified than the teacher your child enjoys now.

Proponents of mandating smaller classes often point to the Tennessee STAR project, in which elementary-school students were randomly assigned either to relatively small classes or to regular classes for four years. An evaluation of the STAR project by researchers at Princeton shows that 40% of regular-class students went on to take a college entrance exam, while 43.7% of small-class students took such exams -- a modest but statistically significant improvement.

However, that program stands in marked contrast to the track record of class-size reduction in the population at large. Tennessee STAR was only a small pilot program that didn’t require the mass hiring of new teachers. When class size reduction has been applied on a large scale, results have been decidedly less promising, because schools must hire many less-qualified teachers to expand the number of classes.

To see this in action, Canadians need only look at the experience of their southern neighbour over the past 30 years. In 1970 there were 22.3 students per teacher in the United States, according to the U.S. Department of Education. Since then the student-teacher ratio has declined steadily, to an estimated 15.1 in 2001. That should mean a big reduction in class sizes. And yet over the same period, test scores for 17-year-olds and graduation rates are both flat.

Why hasn’t large-scale reduction in class sizes been associated with improvements in education? It hasn’t been for lack of spending money -- inflation-adjusted education spending per pupil in the United States has almost doubled since 1970. The most likely explanation is a simple law of economics: If you want to hire more people to do a certain job, you must accept a lower quality of worker.

California’s much-ballyhooed effort to reduce class sizes makes this point abundantly clear. In 1996, persuaded by the Tennessee STAR project that smaller classes would raise its students’ dismal test scores, the state appropriated US$1-billion to reduce elementary school class sizes.

But a Rand Corporation study shows that California students who attended larger elementary school classes have improved at about the same rate as students in smaller classes, and concludes that no link can be shown between smaller class sizes and improvement in test scores.

However, the study did find that smaller classes had produced one major change in California education: a breathtaking increase in the number of people without full credentials serving as teachers. Implementing the new policy required a sudden expansion of state teaching staff -- from 62,226 teachers to 91,112 in just three years. By the time this frantic hiring spree was over, the percentage of teachers without full credentials had jumped from 1.8% of all teachers to 12.5% -- a sevenfold increase.

When class size reduction has been applied on a large scale, any gains from having fewer students in each classroom seem to have been negated by the need to hire less qualified people in order to fill all those newly created teaching jobs. Only two things have been shown to result from large-scale class size reduction: less-qualified teachers and much higher education costs. Why pay more to get less?