658 The Journal of Human Resources
is usually broader than that covered in a specific course and the level of difficulty is typically more appropriate to middle school than to high school. What is needed,
instead, are tests that are external to the school, that relate to the material that teachers are hired to teach, and that the students are likely to take seriously. North
Carolina is one of the few states that have had such tests at the high school level for many years.
3
III. The North Carolina Data
North Carolina has long had a standard course of study for students in all grades, including those in high school. Moreover, since the early 1990s it has
administered statewide end-of-course EOC tests at the high school level. Though EOC tests are given in multiple subjects, we restrict our analysis here to the five
subjects that are typically taken by students in the ninth and tenth grades: algebra; economic, legal and political systems ELP
4
; English I; geometry; and biology. The first three are typically taken in the ninth grade and the last two in the tenth grade,
although many students take the relevant courses in other grades.
5
The EOC test scores carry high stakes for students in that they count for 25 percent of the student’s
grade in the course.
6
We analyze four cohorts of tenth graders—those who were in tenth grade in 1999 2000, 200001, 200102, and 200203.
7
The final sample includes only those students for whom we could match at least three teachers to the EOC tests. That matching
process involves a number of steps because the proctor identified on each student test record need not be the teacher of the course see Clotfelter, Ladd, and Vigdor
2007c for the details. Appendix Table A1 provides information on the matched and unmatched students by subject and cohort. The percentages of all students with
matched teachers taking at least one EOC test who meet the three-test criterion by cohort are 72.6, 77.3, 76.1, and 73.2.
8
In all cases, we have normalized the EOC test scores by grade and by year, with mean zero and standard deviation equal to
one. This normalization implies that the estimated coefficients can be interpreted as fractions of a standard deviation.
3. For an overview of the use of comprehensive tests and end-of-course tests at the high school level in the South, see Southern Regional Education Board 2007.
4. The ELP course has recently been restructured and renamed Economics and Civics. No EOC test was given either for ELP or for Economics and Civics in 2005.
5. North Carolina has four courses of study: Career Prep, College Tech Prep, CollegeUniversity Prep, and Occupational. We believe that most of the students in our sample are in either of the two college tracks,
although some could possibly be in the Career Prep track. 6. Currently, students are not required to pass the exams to graduate. Beginning with the class of 2010,
North Carolina students will be required to pass end-of-course exams in Algebra I, biology, civics and economics, English I and U. S. history to graduate.
7. By selecting these cohorts, we allow each student in any of the cohorts the opportunity to take any one of the five tests. Because our data end in 200405, any student in tenth grade in 200203 would still have
two more years to take the test. For the same reason, our earliest cohort allows us to go back in time so that we can include the students within the cohort who took EOC tests in middle school.
8. The comparable percentages for cohorts outside of our sample are 62.1 percent in 1999 and 68.7 percent in 2004.
Clotfelter, Ladd, and Vigdor 659
IV. Empirical Framework
