MARY LOUISE KELLY, HOST:
To Los Angeles now, where today the school district and the teachers union met for the first time since a strike began on Monday. One of the union's demands is smaller class sizes. And that request is hugely popular with the rank and file, but it has been a sticking point at the bargaining table. As KPCC's Kyle Stokes found, measuring the benefits of reducing class size can be complicated.
KYLE STOKES, BYLINE: It's pouring rain on the picket lines, which makes a regular picket sign impractical.
MICHELE LEVIN: So I have a picket umbrella.
STOKES: Science teacher Michele Levin has etched a union demand on every panel of her white umbrella in bright-pink, waterproof marker.
LEVIN: It will last through rain, sleet and snow.
STOKES: Levin says she teaches 33 students per class at Daniel Webster Middle School, well above national averages. But by LA standards, Levin says a class size of 33 is low.
LEVIN: We're at the whim of the district for class size, and that - I mean, for me, that's the No. 1 reason I'm out here. It's because it's not fair to have so many kids in a class.
STOKES: Her daughter Pilar Cota-Levin goes to one of LA's best high schools, Hamilton High. And she says her largest class has 40 students.
PILAR COTA-LEVIN: Well, it's my math class, and I struggle in math, personally. So I don't get a lot of help. My teacher has to make it so 40 kids can understand.
STOKES: To her mom, the teacher, smaller class sizes mean fewer papers to grade at home. It means Levin can return parents' phone calls. It means she can give more than fleeting attention to each kid in her class. So union leaders say it's not just teachers but students who benefit from smaller class sizes. But from a research perspective, measuring that benefit is complicated.
MATTHEW CHINGOS: Reducing class size is one of the most expensive things you can do in education. So you always have to think about the intervention in the context of what it costs.
STOKES: Matthew Chingos studies education at the Urban Institute. He says the best study on this topic found that students placed in a small classroom of 15 scored better on tests and were more likely to go to college. Compare that with LA today. The district's proposing to spend millions to reduce class sizes. But even after that, most class sizes would still be in the 30s. Core high school classes would be capped at 39. Chingos wonders if that change is worth the cost. He says if the school district has money to spend...
CHINGOS: It's not clear that you would definitely want to spend it on smaller classes versus paying your teachers more or providing more money for new textbooks or for a music program or for after-school activities.
STOKES: School district Superintendent Austin Beutner says it's time for union leaders to consider this tradeoff. He says he, too, wants to reduce class sizes, but the district's also offered teachers up to a 6 percent wage increase, and it doesn't have more money to spend.
AUSTIN BEUTNER: Could we take a portion that's been set aside already for a salary increase and further reduce class size? We'd entertain that notion.
STOKES: The union thinks the district could find the money, but there might be another problem with framing the tradeoff this way. Rutgers University education professor Bruce Baker says in LA, both class size and wages are relatively bad. He says spending on either probably does the district good.
BRUCE BAKER: We're only going to be chipping at the edges on either. And it seems to me - my gut tells me that with class sizes that large, you're probably better off chipping at those edges.
STOKES: And research aside, the ground truth is parents want small class sizes. And the district is competing more and more with private and charter schools that offer them. Declining enrollment has jeopardized the district's finances in recent years, making it harder to pay for a lot of things, including class size reduction. For NPR News, I'm Kyle Stokes in Los Angeles.
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