We study how grouping students of different grades into a single class (multigrading) affects children's cognitive achievement. To do so, we build instruments to identify the causal effect of multigrading by exploiting an Italian law that controls class size and grade composition. We focus on...

We study how multigrading, which is mixing students of different grades into a single class, affects children's cognitive achievement in primary school. We build instruments to identify the causal effect of multigrading by exploiting an Italian law that controls class size and grade composition....

We exploit Italian law DPR 81/2009, which determines class composition, as an instrument to identify the causal effect of grouping students of different grades into a single class (multigrading) on children cognitive achievement. This article focuses on 7-year-old students - those at the...