CARDboard Illustrative Aid to Computation

Cardboard Illustrative Aid to Computation is a way of solving math problems. It involves a piece of cardboard with a grid of squares on it. You can use a marker, like a pencil, to draw pictures and numbers to help you work out the solutions to math problems. It's like a game you can play. You find the answer by shifting and coloring the squares on the grid. This can help you work out math problems, and make them easier to understand.