I made these very simple blocks for my kids, since they are eager to learn the numbers. The blocks have a fixed height and depth of one centimeter and variable width currently from one to 10 centimeters. On the long sides is the variable width imprinted and on the fixed sides a 1. Usual rules and (metric) mesurement tools can be used in conjuntion with the blocks, which my kids love to do. I hope it provides an intutive way to measurements and learning numbers. They can order the numbers themselves bei size and get the order of the numbers. Adding two numbers then can be compared to a longer pice and i.e. verify the result of an addition.
The author hasn't provided the model origin yet.