Yes, a 20-cent Record Can Transform a Math Lesson

Real-world math. If you’re an educator, know an educator, or even if you are a student, you’ve heard about the real-world ad nauseam. I’m quite guilty of using the term. Far too often, that “real world” is something students read about in math problems and not something they experience. As the new school year approaches, I’m beginning to think a lot more about the real world and how I can help students live it in my classroom.

So, I’m working on a unit rate lesson. One of those lessons with the real world on paper. I needed a break, so I decided to visit my local Half-Price Books. I noticed a sign for old records for 20 cents a record. The proverbial light bulb turned on in my brain. I remembered when I used records for a circumference lesson a few years ago. Students were fascinated by the records. Many of them had never seen a record. They wanted to know how the music sounded when a record played. They made me wish I had a record player so they could experience the sound. The connection between those records and circumference may seem a bit far out, but later in the year, students talked about those records in reference to circumference, diameter, and radius. Isn’t that a real-world connection?

I picked up a record. It had two duets by Diana Ross and Marvin Gaye. Yeah, my students would probably give me the blank stare if I mentioned those singers in class. My eyes gravitated towards the length of one of the songs – 2:55. The record wasn’t spinning, but my mind was. My light bulb was getting brighter. I sifted through the records until I found one with 45 R.P.M. on the label. Forty-five revolutions per minute. I thought about the time of the Ross-Gaye duet. I wondered how many revolutions that record spun to play the song from start to finish. I could see my students quickly trying to multiply 2.55 x 45. I would ask them: Does the 55 represent fifty-hundredths or 55 seconds out of 60 seconds? In order to answer this question, it would be easy to type up a problem and print it out. But I want my students to hold records. I want them to look at the times and perform their calculations. Then, I want them to find time length their favorite songs and calculate how many revolutions a record would spin if it included their favorite songs. I started thinking about other record speeds, CD speeds and download speeds. I realized that I could transform my lesson on unit rate and give it a bit of real-world history with a simple 20-cent record.

Truth be told, I spent more than 20 cents. I purchased a class set. The cashier gave me a funny look as I stacked up my set on the cash register. I smiled and told him, “It’s for the kiddos.”  Although I’m not sure if the records could count for bringing technology to the classroom, I’ve been invigorated by the prospect of finishing a good lesson that my students enjoy. Now, if I could only find a record player…