Number Rack, by The Math Learning Center

Developed by The Math Learning Center, 'Number Rack' is a chrome extension designed to nurture the natural progression of children's number sense. It uses movable beads, to encourage pupils to think in groups of fives and tens as a means to discover a variety of addition and subtraction strategies. This virtual version can display up to 10 rows of beads, with 10 beads per row, and offers features like hiding beads, reversing row colors, entering text, editing equations, and sharing work. It is an ideal tool for elementary classrooms and other learning environments.