If you have ever been a cashier, you will relate to this…

At my first job at the Andover Market, we rang up people’s groceries on an electronic register. The machine added everything for us, and gave us a total, let’s say $7.89. We then entered the cash tendered, perhaps $20, and the register would tell us exactly how much change to give back to the customer, $12.11. Easy. they give me a twenty, I give them back twelve dollars, a dime, and a penny. But… Only *one* of the registers could tell us how much to give back, because only one was electronic. The other was an old manual machine that could only give us a total of the items purchased. It did not magically tell us how much change to give back to the customer.

The line for this old register was always long when my friend Shawn ran the register, because he had to write down a math equation and work it out on paper for every transaction. How would you do it? Ask yourself. I would do it the way I was taught in school if no one ever taught me otherwise.

He wrote down the amount they gave him, minus what they owed for their items. And, even though Shawn was considered a “smart kid” in math class, he struggled nervously to do this subtraction while customers stared at him; they tapped their foot while he crossed-out, borrowed, and carried over numbers.This is a difficult task to perform while a customer waits impatiently!

I was lucky, because my mother* (a 9th grade dropout) taught me how to **use the money itself as a tool for counting back change********, and it makes so much more sense!

**As an instructional designer, how would you have me teach Shawn how to make change for customers? What should I do first? I explain below how my mother taught me to make change, but, what is the best way to impart this knowledge to Shawn? What does he actually need to know? What would be the most efficient way to get the knowledge to him? Most effective?**

**By no means do I mean disrespect to my mother. On the contrary! Kids like Shawn are categorized in school as “Smart Kids” because they are good students, not always because they are smart- whatever “smart” means. They are cooperative, willing, and able to follow directions; they do the work the way it was taught to them. They are considered “smart” by school assessments. Does this mean my mother wasn’t smart because she failed 8th grade?*

***To make change, I start with the total of the bill. I say, “$7.89”. By using the smallest change first, I then count up until I reach the next highest coin denominator. So, starting with the pennies, I take one out of the register drawer. This brings me up to $ 7.90. Then I use the larger coins to bring me to the nearest dollar. Add a dime, I am up to $8.00. Then I go to the ones, pulling them out of the drawer as I count them, “$9.00, and $10.00.” I then move to the larger bills. Because I am in the tens now, I can just pull one more ten out of the drawer, and say, “and ten more makes $20.” Of course, I stop at $20, because this is the amount tendered. By counting money back to a customer this way, I am not necessarily aware that I am giving them $12.11. I am acutely aware, however, that I am giving them back the exact difference between the total of what they purchased, and the amount they gave me. I am also acutely aware that I am giving them the largest denominations possible. It is unlikely that a customer would prefer twelve singles and eleven pennies. *

Reblogged this on A Teacher's Portfolio by Layne C. Smith.