Los Angeles high school teacher Glenn Sacks explains why it is important to reduce class sizes and why studies that say otherwise are misleading.

He writes:


As a January teachers’ strike looms, 50,000 teachers, parents, and students marched at a United Teachers of Los Angeles’ demonstration Saturday, demanding that LAUSD address students’ needs. UTLA’s central demand is that LAUSD reduce class sizes. At my high school, for example, we have over 30 academic classes with 41 or more students, including nine English/writing classes as many as 49 students, and three AP classes with 46 or more students. Yet some of UTLA’s opponents assert that class size doesn’t matter, citing studies that did not find a link between class sizes and educational performance.

These studies are significantly flawed. Economist Diane Whitmore Schanzenbach of Northwestern University, a prominent educational scholar, explains:

“The academic research has many examples of poor-quality studies…perhaps the most common misinterpretation is caused by low-achieving or special needs students being systematically assigned to smaller classes. In these cases, a simple correlation would find class size is negatively associated with achievement, but such a finding could not be validly generalized to conclude that class size does not matter or that smaller classes are harmful.”

For example, the current LAUSD norm for Special Education Mild to Moderate classes is 12-14 students. These students take the same standardized tests (albeit sometimes with minor modifications) as General Education students do. To include the small class sizes and low academic performance of these classes to judge the effect of small class sizes on overall student performance is beyond absurd.

Of particular relevance to LAUSD is Schanzenbach’s finding that smaller classes are particularly effective at raising achievement levels of low-income and minority children, and that these students are the ones most harmed by class size increases. Of LAUSD’s student population, 76 percent live in poverty, and 90 percent are minority.

She concludes, “Class size matters. Research supports the common-sense notion that children learn more and teachers are more effective in smaller classes.”

Critics like to cite student-to-teacher ratios—numbers which generally sound reasonable–to make UTLA sound unreasonable. Yet these ratios count special education and other specialized teachers who normally have much smaller classes than regular classroom teachers do. Class sizes are significantly larger than standard student-teacher ratios indicate.

It makes a big difference whether a teacher’s weekly grading ritual involves grading 180 students’ essays and tests or only 125. The extra time it takes to grade those is directly taken away from our students. Every teacher has a long list of things they’d love to do better or more often for their students, if they only had the time. My list includes:

• Call in the disengaged, failing kid sitting in back—the one researchers say is often hit the hardest by large class sizes—and discuss (and then implement) a plan to get them interested in the class.

• Every class has someone like my government student Jonathan, who participates in class with gusto but routinely underperforms on tests. One solution is an oral exam. It’s a legitimate test—if Jonathan doesn’t know his stuff, there’s no way he could hide it from me.

• Students often send me video clips, songs, memes, and articles related to something we’ve studied. When a student connects a lesson to something that they’ve taken note of in current politics, it fuels their motivation and interest. I try to review and (when appropriate) incorporate them into upcoming lessons.

• Going to their athletic or academic events. Students often ask—they like their teachers to see what they’re doing, and it helps teachers build bonds with their students.

• As I grade tests, look for students who have been struggling but who did well, and text their parents the good news. It’s nice to hear a student say, “Thanks for that. It made my mom happy.” It’s also important to share the positives with parents, as opposed to communicating only when there’s trouble.

All of these things take time. The time that excessive class sizes cost us can turn a great teacher into a good one, a good one into an average one, an average one into a struggling one, and a struggling one into an ineffective one.

LAUSD’s own figures show they could reduce class sizes to pre-2008 levels for $200 million — only 10 percent of their current reserve. There’s much debate by educational researchers about various ways to improve our educational system. But there’s no debate about class sizes. Lowering them would be the quickest, surest way LAUSD could help our students.