Geometric Hierarchy of Number
This material is used to represent in geometric form the hierarchy of numbers for: a unit, ten, hundred, one thousand, ten thousand, one hundred thousand and one million. The precise nature of these materials makes it possible to compare by size the decimal categories, visualize through the color-coded system the concept of decimal value and the families of number. A wooden tray for presentation of the 1, 10, 100 and 1000 is included.