Surely you were wondering. While reading about watermelons in the classroom you must have been pondering the more traditional use of watermelons…. as food. Sure, they are interesting objects to be studied, measured and understood, but how did they taste? Let’s face it, no one would bother to grow watermelons if it weren’t for the crush of sweet pleasure inside that rind. Let it be known, the watermelons at OJA did not disappoint. You can’t help but smile when, as soon as knife pierces the outer skin, the “POP” happens. This spontaneous split is really something between a thud, a crack and a splash. These melons were too impatient to be sliced open smoothly. Juicy and sweet. The last taste of summer.
Before melon season is let go for fall, please consider one more academic application for the watermelon. Literature. When life turns the exceptional into the mundane, when the beautiful becomes bland from over-consumption and “WOW” becomes “meh” we can trust writers to remind us of greatness. Through the twist and roll of a poetic phrase a writer can return us to the realization that life is a delicious gift. Watermelons? Consider the words of Pudd’nhead Wilson, one of Mark Twain’s unforgettable characters:
“The true Southern watermelon is a boon apart, and not to be mentioned with commoner things. It is chief of this world’s luxuries, king by grace of God over all the fruits of the earth. When one has tasted it, he knows what the angels eat. It was not a Southern watermelon that Eve took: we know it because she repented.”
You must be thinking this is a stretch. It isn’t really. Aside from the obvious questions about where watermelons originated and the climatic and seasonal requirements necessary to grow these vines successfully, there is an interesting opportunity to use a melon to discuss our planet’s shape and how it’s surface is portrayed in maps. Many times students overlook the subtle but significant differences between globes that sit on a table and flat maps that hang on a wall. Anytime a three-dimensional object is portrayed in a two-dimensional medium, distortion is inevitable. To highlight this distortion students were asked to first draw the continents on small cantaloupes (a surprising challenge very different from drawing them on a sheet of flat paper). These will later be sliced into sections and eaten. The skins will then be spread out on a flat surface to see how this changes our perception of the drawings. A few students were asked to wrap a flat sheet of paper around a watermelon and find the necessary alterations that must be made to the paper to avoid any over lapping surfaces. This was an interesting task as these students had just come from math class where they had been using this same watermelon to discuss the measurement of surface areas. Now they were thinking of this surface area as a map of Planet Watermelon.
We don’t often think of math as a form of communication. Words, not numbers, are usually the first to come to mind when we think of sharing information or ideas. For instance, when we want to tell someone about a newly harvested watermelon many adjectives spring to mind: sweet, juicy, fat, red, striped, delicious etc.. However as soon as we say “bigger than a bread box” we are, even subconsciously, using math as a way to describe or communicate information about our watermelon. Obviously, a bread box is hardly a consistent unit of measurement but it instantly tells you something about our success by way of mathematical comparison .
As part of our Watermelon Math lesson we challenged our upper grade students to think about numerical ways of describing these fruits and using standard units of measurement to communicate their findings. Estimation was a great way to start this exercise. Having students guess, often builds momentum for discovery. It is challenging to describe the chaotic energy of these students as they worked and it’s difficult to measure the “light bulb” moments in kilowatts. They may not remember the formulas they used or the numbers they calculated but hopefully, more importantly, they will think differently about the concepts of circumference, surface area, weight and volume. They will probably think differently about watermelons as well.
Many might say, “Do you really need a watermelon for this exercise?”. Of course not, but if you’ve never brought watermelons into a middle school classroom (which has been watching those melons swell for the last month) you are really missing something. It kind of makes you feel sorry for those poor students who are stuck with measuring styrofoam spheres.
Suppose you had a watermelon patch of a certain size and in that patch your vines had managed to to produce three watermelons. What could you learn from that patch. If this were an average watermelon patch with an average rate of production, you could reasonably conclude that the ratio of the size of that patch to the number of fruit produced in it, would be consistent regardless of scale. If this sounds pretty dry, so far, perhaps it is because you are not standing in a watermelon patch. Putting yourself right in the middle of a word problem (excuse the hyperbole) changes everything. The first thing that changes is the “will this be on the test?” mentality. Math becomes a conversation springing from curiosity and not a lecture. The students become the ones asking the questions and the teacher starts guiding rather than dragging. This is what edible education is all about and this is what math in the garden looks like.
This was just the beginning. These students learned something more important than the answers to specific math problems. They started to see how math can be applied. After all, what good is information without application? Hopefully there will be more to learn from these watermelons. Maybe if we put one watermelon on a train headed west from Chicago and another on a train headed east from San Francisco ……..