This study investigated the development of length measurement ideas in students from prekindergarten through 2nd grade. The main purpose was to evaluate and elaborate the developmental progression, or levels of thinking, of a hypothesized learning trajectory for length measurement to ensure that the sequence of levels of thinking is consistent with observed behaviors of most young children. The findings generally validate the developmental progression, including the tasks and the mental actions on objects that define each level, with several elaborations of the levels of thinking and minor modifications of the levels themselves.
Janka Szilágyi, Assistant Professor, Department of Education and Human Development, The College at Brockport, State University of New York, 274 Brown, 350 New Campus Drive, Brockport, NY 14420; email@example.com
Douglas H. Clements, Kennedy Endowed Chair and Professor in Early Childhood Learning, University of Denver, Educational Research, Practice and Policy, Morgridge College of Education, Katherine A. Ruffatto Hall 514, 1999 East Evans Avenue, Denver, CO 80208-1700; Douglas.Clements@du.edu
Julie Sarama, Kennedy Endowed Chair in Innovative Learning Technologies and Professor, University of Denver, Educational Research, Practice and Policy, Morgridge College of Education, Katherine A. Ruffatto Hall 514, 1999 East Evans Avenue, Denver, CO 80208-1700; Julie.Sarama@du.edu