This paper, published by Stanford University’s Center for Education Policy Analysis, examines a sample of middle school (Year 7-9) children who were quasi-randomly assigned to either a maths remediation class schedule (taking two maths classes for one entire school year) or to a regular class schedule (taking one maths class and one class in some other subject). Findings showed that increasing the amount of time struggling pupils spend in maths classes did improve maths test scores, but the gains did not last in the long run.
Pupils were identified for the extra class if they scored below the 50th percentile on the 5th grade (Year 6) state maths test. Pupils who scored above the cut-off had just one maths class. For the roughly 80,000 middle school pupils in the sample county, the author obtained data on their annual test scores, class schedules, and demographics from 2003 to 2013.
At the end of the year, students who had double maths scored higher than their peers who had only one maths class. However, one year after returning to a regular one-class schedule, the initial gains decayed by as much as half, and two years later just one-third of the initial treatment effect remained.
The author concludes, “This pattern of decaying effects in the years following treatment is similar to alternative strategies for improving achievement, like reducing class size or improving the effectiveness of teachers. That similarity suggests a need to reconsider whether current remedial education strategies – characterised by short-lived increases in the quantity of instruction – are a cost-effective way to raise the maths achievement of students who currently lag expectations for their age.”
Source: Spending More of the School Day in Math Class: Evidence from a Regression Discontinuity in Middle School (2014), Journal of Public Economics, 117.