This report studies the impacts of a tracking program in a large urban school district that establishes separate “gifted/high achiever” (GHA) classrooms for fourth and fifth graders whenever there is at least one gifted student in a school-wide cohort. Since most schools have only a handful of gifted students per cohort, the majority of seats are filled by high achievers ranked by their scores in the previous year’s statewide tests.
The authors find that participation in a GHA class leads to significant achievement gains for non-gifted participants, concentrated among black and Hispanic students, who gain 0.5 standard deviation units in fourth grade reading and math scores, with persistent effects to at least sixth grade. Importantly, they find no evidence of spillovers on non-participants.
They also investigate a variety of channels that can explain these effects, including teacher quality and peer effects, but conclude that these features explain only a small fraction (10%) of the test score gains of minority participants in GHA classes. Instead we attribute the effects to a combination of factors like teacher expectations and negative peer pressure that lead high-ability minority students to under-perform in regular classes but are reduced in a GHA classroom environment.