Follows students' natural progression from measuring with informal or non-standard units to using standard units to measure such attributes as length, weight, a

CD-ROM contains: Blackline masters for some of the activities illustrated in text -- Applets for students to manipulate -- Resources for professional developmen

Children in prekindergarten focus on counting and gradually master the essential one-to-one matching of an object to a number. By the end of second grade, they

Do your students suppose that 1/3 is greater than 1/2, since 3 is greater than 2? Do they believe that having “halves” means having two, and only two, congr