Do college students benefit from entering high-ability classes?

College students placed in "high-ability" classes have lower grades and graduation rates, according to a new study from Cornell University

The study, conducted by Assistant Professor Evan Riehl of the ILR School, looked at students who were barely qualified to take classes with high-achieving peers at a major university

In the long run, marginal students admitted to high-ability classes passed an average of four fewer college courses, and they were nearly nine percentage points less likely to earn a degree

Tracking - grouping students into different classrooms or different schools by ability - is a common but often controversial practice that applies to all levels of education

Riehl's findings are quite the opposite

"Tracking is pervasive at all levels of education," Riehl said

In the paper, Riehl and his co-author, Nicolás de Roux of the University of Los Andes, studied the admissions system at Univalle, a prestigious university in Colombia, tracking admitted students into high- and low-ability classes in the same major

Typically, students apply to specific majors at Univale University in batches in the fall or spring, and admission is based solely on scores on state standardized tests

"Students are on the verge of admission for the fall or spring classes, so we can compare those who narrowly made it to the fall class to those who narrowly missed out and were placed in the spring class," Riehl said

"That means they're in the same school, taking the same course, usually taught by the same teacher, just a semester apart, but students who start in the fall have higher-ability peers, " he said