The rekenrek is a great tool for early math classrooms. Its deceivingly simple design—two rows of ten beads, five red and five white—might leave some wondering how to use a rekenrek. Teachers in our Innovations Program sister schools have used the rekenrek as a visual aid while teaching students to count on. Others have turned attendance-taking into a math learning opportunity by counting one bead for each student present. Rekenreks are also frequently used to practice number sense, as the organized rows of red and white beads are well-suited for subitizing.
The video above gives a great overview of how to use a rekenrek. It also provides a few specific examples of problems that you could give to your students.