Many of North Carolina’s largest school districts have debated and/or implemented policies that route a significant number of eighth-grade students into Algebra I, a course that traditionally reserved for ninth-graders.  Earlier this year, for example, members of the Wake County school board clashed over middle school math placement policies.

The National Bureau of Economic Research (NBER) just published a fascinating study by Duke University professors Charles Clotfelter, Helen F. Ladd, and Jacob Vigdor, titled “The Aftermath of Accelerating Algebra: Evidence from a District Policy Initiative.”

The NBER study focused on a short-lived (2002-2004) Charlotte-Mecklenburg Schools (CMS) initiative to assign “moderately-performing students” to algebra courses in eighth-grade.  The authors “examine whether acceleration increased the likelihood that students would stay on track to pass three college-preparatory math courses – Algebra I, Geometry, and Algebra II –within six years of beginning seventh grade.”

Clotfelter, Ladd, and Vigdor found that students participating in the acceleration initiative scored significantly lower on state Algebra I tests and were significantly less likely (or no more likely) to pass subsequent Geometry and Algebra II courses in a timely way.  The authors address several possible causes for those outcomes.

1. Administrators increased class size to accommodate a larger number of algebra students.

Mean class sizes actually decreased the year after implementation.

2. Administrators assigned less qualified and less experienced teachers to Algebra I courses.

This did occur but the effect was small.

3. The elimination of CMS’s race-based busing program in 2002 compromised the quality of instruction for the group of students targeted by the acceleration initiative.

Nope.  The researchers concluded, “As we detail below, however, we obtain very similar results from an analysis of a similarly-timed algebra initiative in North Carolina’s third-largest school district [Guilford County Schools] which did not simultaneously change its busing policy.”

4. The authors speculated that the presence of moderately-performing students decreased the overall instructional quality.  This would have affected the performance of moderately-performing students relative to their high-performing peers.  The authors pointed out, “Such a mechanism would actually lead us to understate the negative impact of accelerating algebra.”  In other words, simply placing lower-performing students in classes with higher-performing students may have had negative consequences for both populations of students.

The data did not permit researchers to explore peer effects.

So, there was no evidence that class size, teacher quality, and student assignment changes produced significant declines in mathematics performance for the moderately-performing students who participated in the acceleration initiative.  The authors suggest that an initial redesign of the entire mathematics curriculum may have produced different outcomes.