Does Detracking Work? Evidence from a Mathematics Curricular ...

Detracking 32Towering Pines’ experience with curricular intensification in middle school mathematics as acase study to understand the implications of curricular intensification more broadly.Specifically, we address three questions: 1) Did the 8 th grade Algebra for all policysucceed in placing more students into higher level mathematics courses; 2) How did the reformsaffect the social organization of schools; and 3) What effects did the policy have on students’mathematics achievement?We find that the push to place 8 th graders into Algebra had lasting impacts on students’course-taking trajectories, raising the odds that Towering Pine students enrolled in academicmath courses in both 8 th and 10 th grades. Thus, we conclude that the policy was successful in itsstated goal. Further, the policy diluted the effect of previous achievement on course placement,so that 7 th grade mathematics achievement is less predictive of 8 th and 10 th grade course-taking inlater cohorts.Decoupling prior achievement from course placement resulted in a substantial decline inclassroom level mathematics skill based segregation. We also find that skill heterogeneityincreased in the district’s Algebra and Geometry classrooms. Together with the declines that weobserve in the average skill level of peers at all three course levels, this suggests that curricularintensification made Algebra and Geometry classes grow less select and thus more variable.Thus, in answer to our second question, we conclude that curricular intensification partiallydetracked mathematics education in the district.Finally, we examine the impact of curricular intensification on mathematics achievement.We find that students at the top of the distribution do not appear to experience long term declinesin scores, though it is possible that large changes in course enrollments might have led to a onetime drop in scores at the top of the distribution. Thus, detractors’ claims that detracking will