Achievement flourishes in larger classes: Secondary school students in most countries achieved better in literacy in larger classes

Abstract

There is no consensus among academics about whether children benefit from smaller classes. We analysed the data from the 2012 Programme for International Student Assessment (PISA) to test if smaller classes lead to higher performance. Advantages of this data set are not only its size (478,120 15-year old students in 63 nations) and representativeness, but also that the 2012 PISA data set for the first time includes the class size for each participating child. We found that in most countries, children in smaller classes had a lower performance score in solving reading comprehension problems than those in larger classes. We further analysed the relation between class size and factors that can explain this paradoxical phenomenon. Although grouping of students by ability and the socioeconomic status of parents played some role in some countries, these factors cannot fully explain this effect. We finish discussing the overlooked potential advantages of larger classes.