do peer effects matter? nah

There’s long been a belief that peer effects play a significant role in how well students perform academically – that is, that learning alongside higher-achieving peers likely helps students achieve themselves, while learning alongside lower-achieving peers might drag them down. Is that the case?

Probably not. The newer, larger, higher-quality studies don’t show evidence for that in quantitative outcomes, anyway. A large study looking at exam schools in New York and Boston – that is, selective public high schools in large urban districts – found that even though enrolling in these institutions dramatically increased the average academic performance of peers (thanks to the screening process to get in), the impact on relative performance was essentially nil. That’s true in terms of test metrics like the PSAT, SAT, and AP Scores, and in terms of college outcomes after graduation. It just doesn’t matter much. A study among students transitioning from the primary school level to the secondary school level in England, where dramatic changes occur in peer group composition, found a significant but very small effect from peer group in quantitative indicators. Like, really small. Assuming the null is a pretty good bet in a lot of education research.

Of course, none of this means there’s no human value in sending your kids to school with elite peers. There are many things that matter in life beyond quantitative education indicators. (Though you’d never know that if you listen to some pundits.) Your kids may find their school experience more pleasant, and it may help them network later in life, if they attend school with high achievers. On the other hand, it will inevitably increase the homogeneity of their learning environment, which seems less than ideal to me in a multicultural democracy like ours. Public schools that are struggling desperately need financial secure parents who have the social capital necessary to advocate for them, too. Either way, though, if you’re worrying about how peer effects will impact your kid’s outcomes, you shouldn’t. Like an awful lot of things that parents worry about when it comes to their children, it just doesn’t matter much.