Yesterday, I tutored a 5th grade student in math. Julie is a smart girl but sometimes lacks confidence in her math skills. Her mother wanted her to work on ratios and percentages. I decided the math lesson would be more “real” if we worked with cents, dimes, nickels and quarters to learn percentages. After all, percent means per hundred. Our lowly penny is a cent, meaning one-hundredth. So it’s not hard to figure out that a penny/cent is 1% of a dollar. You need 100 of these to make a dollar. The math is written: 100 x .01 = $1. So one penny is 1/100 of a dollar. Divide 1 by 100 and you’ll get 1%.
On the kitchen table, I scattered handfuls of pennies, nickels, dimes and quarters. After we figured out a penny was 1% of a dollar, we went on to quarters. Every child knows four quarters make a dollar. We represented a quarter as a fraction: ¼ and then divided 1 by 4 .and got .25 or 25%. Two quarters represented 2/4 or 1/2 or 50% of a dollar. Three quarters represented 3/4 or 75%. With each of these computations, Julie handled the money, sliding it in place for the various math problems. We then worked with dimes (its root word means ten) and nickels. Interesting we have one coin named after the metal it’s made of. As a child, I had difficulty understanding a nickel which is larger than a thin dime was worth one half of a dime! So working with coins, we figured out percentages.
Then we turned to ratios. I’d scatter an assortment of coins on the tabletop. “How many of the 12 coins are quarters?” I’d ask. We’d write the ratio: 3/12 and figure out the percent. Then I had Julie scatter the coins herself and make up her own percentage problems.
So when you have the opportunity, make math real by having real objects to illustrate the math lesson.