Isn’t it interesting how inspiration can come from the
simplest things? Several years ago, I was at the grocery store when it hit me…the
corn. At first, I didn’t understand why something I’m familiar with totally
occupied my mind and my shopping experience. It wasn’t too long before I
figured it out; I found a new way to introduce rational numbers to my students.
I selected seven ears of corn (6 for my classes and 1 for practice) and planned
for a great day of learning.
Okay, I have to admit my kids thought I was a little
crazy when they walked into the room and saw a plastic covered desk in the
front of the classroom with corn on top of it. I had even gone as far as to
borrow protective eyewear from one of the science teachers. When my students
settled down, I held up a piece of corn and asked them to think about the
relationship between corn and rational numbers.
The majority of students focused on the weight of corn
and the cost. I was happy with their thinking and their discussion, but I was
going in a different direction. I held up the ear of corn and told them to
think about it as a whole number. While I’m certain some of my students wanted
to get the counselor and check on my well-being, they stayed in their seats. We
discussed whole numbers and examples of whole numbers. Then, I took out the
knife.
Eyes widened as I chopped the corn into four pieces. I held up one of the sliced sections and asked, “If an ear of corn represents a whole number, what do these sections represent?”
This time, the kids were ready! We talked about how the
four parts made up the whole. Yep, those were the fractions. Recognition - and
a little bit of excitement - began to fill the room. I knew I had hooked them. Before
I could finish revealing those precious little kernels, hands shot up because
my students knew the question I was going to ask and the answer to that
question.
Yes, those kernels represent decimals. 
In some classes, we even discussed what the silk could represent. In my own humble opinion, silk is totally irrational (those of you who have shucked corn may understand what I mean). Anyway, corn became a successful theme for my rational numbers unit. So successful, in fact, that I’ve used it ever since. I think of it as a “sticky” lesson because the concept sticks with students based on the way it is delivered.
There are many unconventional ways to enhance student
learning, and this is one of my favorites. What are some unconventional ways
you teach rational numbers?
Read my previous blog post about creating review posters
for more information about using corn in the classroom: http://route22edu.blogspot.com/2015/04/creating-posters-for-reviewing-concepts.html
