Number Rack, by The Math Learning Center

Develop number sense and explore addition and subtraction strategies.

Number Rack facilitates the natural development of children’s number sense. The movable, colored beads encourage learners to think in groups of fives and tens, helping them to explore and discover a variety of addition and subtraction strategies. This virtual version of the manipulative is an open-ended educational tool, ideal for elementary classrooms and other learning environments. The number rack is a key component of Bridges in Mathematics, second edition. Online preview available. Visit The Math Learning Center for more information about using the Number Rack, including a free activity guide: www.mathlearningcenter.org/apps. App Features • Display 1 to 10 rows of beads, 10 beads per row. • Hide beads with resizable shades, which allows teachers or learners to model subtraction or difference problems. • Reverse the colors of rows 6 to 10 to distinguish (or not) groupings of 25 beads. • Enter text directly from your keyboard with the writing tool. Add labels, descriptions, or instructional text to your work. • Edit equations and other math text using a traditional text field. • Add drawings on the workspace to explain thinking. • Share your work by saving an image or url, or providing a sharing code to others. Great for creating the initial setup of an activity, then sharing it with students so they can explore it further.