DESCRIPTION: (Adapted from applicant's description) The primary objective of the Research Core is to assist the Research Subprojects by providing professional expertise and service in the design, development, and support of measures, tests, assessments, protocols, and other data collection instruments, placing special emphasis on addressing issues in developing assessments specifically designed for Spanish speakers learning English. The Research Core will also support cross-project coordination in the analyses and interpretation of research outcomes through such activities as providing comparison information on the levels of performance achieved by groups of children with different amounts of exposure to Spanish and English, respectively.