How to Teach the Basics of Percentages for Children
To learn how percentages are calculated it is very important for students to understand the meaning of percent, how to visualize it and it's relation to decimals and friactions.
Let's check that the "cent" part of the word "percent" means "100" can be a great starting point. In other words, the word “percent” means "per 100." Also it's very helpful if you relate percents to everyday activity. For example "What does it mean to eat 50 percent of a banana?" or "If 10 percent of 100 candies fit in the cup, what does that mean? How many candies would that be?” Starting with these kind of questions will make the learning process much easier.
Use grids to visualize percents
If we use grids of 100 squares to visualize percents, we can demonstrate the “parts” and the “whole.’ So the children color 20 small parts out of 100, they can visualize 20 percent. In case they color in all 100 parts, then they have colored 100 percent of the grid or an entire large square. The best way to simplify things is to use a 10-by-10 grid. Children can create their own designs by color and then compute the percentage of each color. This way of visualization engages the children and promotes understanding.
What about 200 percent?
In many cases, a number like 200 percent could be confusing, because they might think that the value means 200 times more. In this case using two large squares, both divided into 100 parts, children can see what percents over 100 means visually. Filling in 100 of the first large square and 25 of the second square will equal 125 percent. If a child thinks the answer is 125 out of 200, explain him that percent refers only to parts out of 100. Once all 200 smaller parts are filled in, it will be clear that he has filled in two large wholes. In conclusion, 200 percent refers to two large squares, not 200.