Teaching Exponential Math Using the Pandemic as an Example

With so many school closures, parents are becoming increasingly responsible for their kids schooling at home. One topic that parents might consider exploring with their kids is the idea of exponential math in relation to this pandemic.

There’s been a lot in the news about the exponential rise in the number of cases of the coronavirus in several countries (including the United States), with various charts showing the lines and curves upon which the fate of nations depend. Here’s a simple activity you can do with your kids to help them understand the idea of exponential math, where values of new cases of coronavirus in this instance, double over a given amount of time.

Clear a space in your living room (or another room that isn’t too encumbered by furniture), and then get some masking tape and make an ”L” configuration with the lines equal in length (perhaps 10-12 feet long each way). Then get out a ruler and a pen or pencil and segment each masking tape line into say, one foot intervals. The line that is horizontal is now the ”x” axis (put x at the left end of the tape) and represents days gone by during the pandemic and the vertical line is the ”y” axis (put y at the bottom of the tape) and represents number of new cases of the coronavirus.

Have your child physically place themselves exactly where the x and y lines come together, which would be represented as Cartesian coordinates (1,1). [Note: this means we’re starting with day 1 and 1 one person]. Then, have them move one interval to the right along the ”x” axis, signifying that one day has gone by (day 2). To signify a value of double 1, or 2 cases of coronavirus, have your child then move ”up” two intervals parallel to the ”y” axis. One day has passed, two cases of coronavirus (2,2).

Then have your child move one more interval to the right along the ”x” axis (another day passed), and this time move four intervals ”up” along the ”y” axis (doubling the previous amount), indicating that four cases of coronavirus have been detected (3,4). Then another interval to the right (the fourth day), and sixteen intervals up (doubling the previous figure) (4,16), a further interval to the right (the fifth day), and 32 cases of coronavirus (5.32). At this point you’ve probably run out of paper and space, but if you’re adventurous, consider continuing to map it into the next room!

If you want, you can keep track of the ”curve” with a ball of yarn, fixing the yarn at each interval with a small piece of masking tape. You can compare this type of exponential growth curve with a line showing linear growth (for each day of the coronavirus, in this case, you can go up the ”y” axis one interval, signifying one new case per day (1,1) or any fixed number of cases per day) (2.2), (3.3), (4.4) etc..

After you’ve done this exercise, you can take a look at some actual curves from the news, showing the different curves for the U.S., China, Italy, Spain, and/or other countries. Note with your kids the differences in the curves as some countries are seeing doubling take place every two or three days, and in other countries the curve becomes ”flatter” as new cases decrease over time. These graphs are now likely to make a lot more sense to your kids than they did before. Especially for the children who learn best through their bodies!

For more information on learning math, reading, and other subjects in innovative ways, see my book In Their Own Way: Discovering and Encouraging Your Child’s Multiple Intelligences.