(Preview of things to come not yet available in video lessons)
Percentage is done in a very interesting way in Shape Math™. The representation of one, the 1 triangle, has a special shape that can break it down into 10 parts. Each of these 10 parts can be broken down further as needed using the same shape. This is not usually needed.
This technique can help the student do practical things like calculating a tip. Each part of the 1 triangle represents 10% of the dollar. If your bill was $10 you would group together two groups of ten to make 20%. Do this for each dollar that the meal cost. Each time you complete a one triangle you have another dollar so the tip equals two dollars.
It visualizes the very abstract process of multiplying by a decimal. There are advanced techniques to calculate large bills more quickly. The student will no longer have to rely on a cell phone calculator or their friends to tell them how much to tip. This kind of independence helps increase one’s self-esteem.