The purpose of this paper is to assess the effects of this increase in the mandated minimum number of math courses. This assessment entails two separate questions. One is whether the policy affected actual course-taking among high school students. In exploring this question, we are attentive to the likelihood that the new standard might have a bigger effect on some groups of students than on others. Another question is whether any such changes in high school course-taking, together with the threat of being denied admission, affected college enrollment patterns or students’ choices or performance once enrolled.

Our findings fall into three groups. First, the evidence is consistent with the expectation that the increased requirements would influence the number of high school math courses taken by at least some students. Throughout our analysis we characterize students by their math aptitude as measured by their performance on the required 8^th grade math end of grade test, with performance divided into deciles from low to high.  Many students, particularly those at the higher deciles, were already taking four math courses by the time the minimum number was increased, so the new requirement presumably had no direct effect on them. But in eight of the 10 deciles we observed greater-than-expected increases in the share of students who, using the proxy we had (whether a student had taken Algebra II by 11^th grade), were in a position to meet the new four-course standard. We cannot prove that these increases were due to the policy, but it is reasonable to think that at least most of them were.

Second are findings related to whether the increase in math courses affected whether students enrolled in one of the state’s public university campuses and, if so, where. Because the increases in math courses were greatest for students with 8^th grade math scores in the middle deciles, one might have expected that the branch campuses whose students traditionally come from those deciles would have experienced the biggest increases in enrollment due to the changes in math course taking in high school. Surprisingly, we did not find that. Instead, we find increases in predicted enrollment due to changes in math course taking across all campuses, distributed differently across math achievement deciles. Each branch experienced increases in predicted enrollment, but those increases tended to be for students in the deciles that were already most common at those branches. For the branches that have traditionally drawn from deciles below the median, the newly stimulated enrollments came from those deciles. For the two branches with the highest shares of students from the top deciles before the policy change, the new policy stimulated new enrollment, and it was mainly in those same top deciles. Despite the general tendency before the change for top-decile students to have taken four math courses, many top decile students apparently had not been doing so, especially in school districts that had not pushed such students to do so in the past. Once the policy change was enacted, such districts beefed up their math pathways, causing more top students to take more math. Conceivably, the new requirement caused these top students to consider attending the leading research universities at Chapel Hill or NC State instead of one of the branches closer to their homes.

The third set of findings relate to whether the minimum course requirement affected the behavior of students once they enrolled in one of the branches. Here the results are less broad-based than for the other analyses.  We find some evidence that the policy change increased the likelihood that high decile students would major in a STEM field, but reduced the likelihood of low decile students of doing so.  Further, we find that the program raised the GPA of students in deciles 8 and 9, but had at most limited effects on four-year graduation rates.