The benefits of small classes — more individual attention, less teacher stress — may not outweigh the costs in dollars and teacher quality, concludes The Opportunity Cost of Smaller Classes, a state-by-state analysis by the University of Washington’s Center for Reinventing Public Education. Call sizes in 2011-12 were slightly smaller than in 1999-2000, countering “the common and mistaken belief — spurred on by knee-jerk sensationalism and politicking — that class sizes are ‘skyrocketing’,” writes Education Gadfly.
The authors demonstrate that increasing the nation’s average class size by just two students could free up $15.7 billion—enough to raise average teacher salary by $5,000 per teacher, provide a laptop for every student, or lengthen the school day in the poorest quintile of schools.
Limiting K-3 class size to 14 to 17 students in high-poverty elementary schools showed lasting benefits, especially for blacks, in the Tennessee STAR study. (Some argue all the benefits accrued in kindergarten and first grade.)
Inspired by STAR, California paid all elementary schools $1 billion-plus a year to lower class sizes to 20 in K-3. Suburban schools were able to hire competent teachers for the new classes. Urban schools with hard-to-teach kids filled classrooms with less-qualified candidates, a follow-up study found. The study found no evidence smaller classes improved student achievement. Because of the very high costs, schools spent less on other needs, including maintenance, teacher training, libraries and technology. Music, art, sports and special ed lost space on campuses. (I’ve seen schools cover their playing fields with portable classrooms.)
“Very large class-size reductions, on the order of magnitude of 7-10 fewer students per class, can have significant long-term effects on student achievement . . . in the earliest grades, and for students from less advantaged family backgrounds,” write Brookings’ Russ Whitehurst and Matthew Chingos. But is it the best use of education dollars? “One careful analysis of several educational interventions found CSR to be the least cost effective of those studied.”