This document examines the use of measurement tools to evaluate children's psychological development. The first part of the document discusses the identification and quantification of developmental landmarks and the reasons for evaluation. The second part reviews several evaluation instruments. The Ruth Griffiths mental development scales are used to measure psychological development in infants and young children. The Kohs block test and Florence Goodenough draw-a-man test assess nonverbal intelligence in young children. Children's vocabulary is measured by the Binois-Pichot test. The Wechsler Intelligence Scale for Children--Revised assesses the intelligence level of school-age children. Limitations of these tests are noted. Other methods of evaluating children's development include the use of health record books, professional observation, interviews, questionnaires, and a combination of instruments. The third part of the document discusses the use of assessment results and the relationship of developmental evaluation to educational programs. Appendixes include a French health record book, an observation guideline for small children, and a description of a child development research project in Argentina. A 16-item bibliography is provided. (BC)