This analysis uses data from the Education Longitudinal Study of 2002 (ELS:2002), which was designed to provide trend data about critical transitions experienced by students as they proceed through high school and into young adulthood.3 This nationally representative study of 17,590 students who were 10th-graders in 2002 was conducted by the National Center for Education Statistics (NCES).4 ELS:2002 used a two-stage sampling procedure. In the first stage, a sample of 750 high schools, both public and private, were selected with probabilities proportional to their size. In the second stage, approximately 26 students were randomly sampled from each school on the condition that they were in the 10th grade in the spring term. Of the 17,590 eligible students, 15,360 completed a survey about their school and home experiences (87 percent weighted response rate), of which 14,540 completed cognitive assessments in mathematics and reading (95 percent, weighted response rate). Their parents, teachers, principals, and librarians were surveyed as well. In the spring of 2004, about 14,710 of the originally selected sample members were reinterviewed and comprise the target population for this study: sophomores in the spring of 2002 who were respondents in both the base-year (BY) and first follow-up (F1) interviews. Their high school transcripts were collected in 2004–05 and they were reinterviewed in the spring of 2006 (2 years post on-time high school graduation).5
To be included in this analysis, sample members had to have been an in-school sophomore in 2001–02, participated in both the BY and F1 interviews, completed the mathematics assessment in the BY and F1 interviews, and had complete transcript information for the 2002–03 and 2003–04 academic years. Of the 14,710 base-year sophomores who participated in both the BY and F1 interviews, 13,330 participated in the BY mathematics assessment, of whom 9,920 participated in the F1 mathematics assessment.6 Only students who remained in their base-year schools were administered the F1 mathematics assessment. Scores were imputed for students who transferred to a new school or were still enrolled in their base-year school but were unable to participate during the in-school test administration. However, because mathematics achievement is the key variable in this analysis, these cases with imputed test scores were excluded to prevent any error in estimating learning and learning gains. Lastly, 330 cases were excluded because they had no transcript information and 130 cases were excluded because they lacked evidence of both a mathematics course and complete transcript information for both the 2002–03 and 2003–04 years.7 The final analytic sample includes 9,460 respondents, or about 64 percent of the approximately 14,710 members of the sophomore cohort who participated in both the base-year and first follow-up interviews. A bias analysis comparing the sociodemographic composition of the analytic sample (n = 9,460) with the full sophomore panel sample (n = 14,710) is presented in section A.6 of appendix A. Compared with the full sophomore panel sample, there are higher proportions of White students, students who expect a bachelor's degree or higher, and students living with both their father and their mother in the analytic sample. All estimates are weighted with the panel weight (F1PNLWT) and generalize (with the above qualifications about inclusion conditions) to the population of students who were sophomores in the spring of 2002. In all analyses, standard errors were adjusted for the clustered and stratified sampling design using Taylor-series linearization methods (StataCorp 2004).
