Traditionally, modeling student retention has been done by deriving student success predictors and measuring the likelihood of success based on several background factors such as age, race, gender, and other pre-college variables, also known as the input-output model. Increasingly, however, researchers have used mediating factors of the student…

In 2002/03, the Charlotte-Mecklenburg Schools initiated a broad program of accelerating entry into algebra coursework. The proportion of moderately-performing students taking 8th grade algebra increased from less than half to nearly 90%, then reverted to baseline levels, in the span of just six age cohorts. We use this policy-induced variation to…