A great visual aid for the demonstration number concepts on the whiteboard. Promotes composing and decomposing numbers, develops numbers sense and base-ten concepts, and operations skills (addition and subtraction). Ten frames can be used to develop students' subitizing skills, the ability to " instantly see how many" . This skill plays a fundamental role in the development of students' understanding of numbers. Teachers and students will engage in base ten, operation skills and other number skills as a group or center activity. Set includes 2 magnetic foam Ten-Frames and 20 disks (10 red and 10 yellow disks). Foam makes it easy to remove pieces from white board. Each Ten-Frame measures 5" x 12-1/4" .