Introduction

Analytic Sample

The findings in this report are based on 10,500 public and private school children who entered kindergarten for the first time in fall of 1998 and were administered the English version of the ECLS-K cognitive assessments in the fall of 1998, spring of 1999, spring of 2000, and spring of 2002.²⁰ Estimates in this report may not exactly match those of previous ECLS-K reports on young children?s achievement (West, Denton, and Germino Hausken 2000; West, Denton, and Reaney 2001; Denton and West 2002). This report uses data for respondents assessed in the fall and spring of kindergarten, spring of first grade, and spring of third grade, so a different weight was used to produce estimates than was used in earlier reports. The weight in this report is stricter in its response requirements compared to some other reported analyses and, thus, utilizes a slightly smaller sample of children due to attrition. In addition, the ECLS-K IRT-scale scores are recalibrated after each round of data collection. The assessment score variables used in this report all come from the ECLS-K Third Grade restricted-use data file, which includes the recalibrated scores for all rounds of data collection. Further, this report is based on all first-time kindergartners? performance in their fourth year of school, not only those who were in third grade in the spring of 2002. Therefore, this report includes some children who were excluded from the earlier ECLS-K report, Children?s Reading and Mathematics Achievement in Kindergarten and First Grade (Denton and West 2002), because they did not progress to first grade in the spring of 2000.

This report focuses on those children who were assessed in English at all points in time. Prior to administering the English reading and mathematics assessment in kindergarten and first grade, children?s English language proficiency was evaluated. Children whose home language was other than English (as determined by school records) were administered the Oral Language Development Scale (OLDS) (for more information, see the ECLS-K Base-Year User?s Manual, National Center for Education Statistics 2001). If children demonstrated sufficient proficiency in English for the ECLS-K direct child assessment, they received the English reading and mathematics battery. Approximately 68 percent of Hispanic children and 78 percent of Asian/Pacific Islander children were assessed in English in the fall and spring of kindergarten and in the spring of first grade (Denton and West 2002).²¹ In the fall of kindergarten, 1,567 children were not administered the English battery because of their performance on the OLDS. By spring of first grade, this number was down to 350.²² In the third-grade year, the OLDS was not administered and all children were assessed in English.²³

Table 1 provides a comparison of the population of children represented by the sample used in this report and the full ECLS-K population of firsttime kindergartners. The analytic sample used in this report has a larger percentage of White²⁴ children (64 percent) and a smaller percentage of Hispanic children (13 percent) than the full ECLS-K sample of first-time kindergartners (59 and 18 percent, respectively), and the percentage of children with no risk factors is higher for the analytic sample than the full sample (62 percent vs. 58 percent) Differences between the racial/ethnic and the risk factor index distributions of the analytic sample and the ECLS-K population distributions are due, in part, to the exclusion of children who were not administered the assessments in English at all time points in the study.