This report presents the results of a federally mandated study done to determine the best means of identifying, locating, and counting homeless children and youth, for the purpose of facilitating their successful participation in school and other educational activities. Several alternative approaches to obtaining consistent national estimates of the number of homeless children and youth, their educational needs, and their living situations are examined. These methodologies were designed to be implemented at the national level. This document describes possible data sources and information needs; four practical alternatives for the design of national estimation studies (the best of which involves primary data collection with service using and non-service using street homeless people, plus additional questions attached to an on-going national survey); cost estimates for various methods, for combinations of methods, and for a special study to enumerate homeless street youth; methods of obtaining annual estimates for homeless children and some youth; and scheduling issues for a national data collection effort. Included are six exhibits. An appendix contains bid specifications and instrument guidelines. (JB)