“…These features include the consequences of class size (Angrist and Lavy, 1999;Angrist et al, 2019;Chetty et al, 2011;Krueger and Whitmore, 2001), teacher quality (Chetty, Friedman, and Rockoff, 2014;Rothstein, 2017), effects of tracking by initial achievement conditional on teacher incentives (Duflo, Dupas, and Kremer, 2011), and peer effects over a range of dimensions. These peer dimensions include the long-run negative effect on earnings from exposure to disruptive peers (Carrell, Hoekstra, and Kuka, 2018), extensive non-linearities in peer ability effects, a positive link between low-achieving Kindergarten peers and non-cognitive skills (Bietenbeck, 2020) and between academic achievement and peers' persistence (Golsteyn, Non, and Zölitz, 2020), positive spillovers from friends' educational aspirations (Gagete-Miranda, 2020;Norris, 2020), and the effects of a variety of peer compositions on educational attainment.…”