No Green Thumb Here
by John Pearson
Every year, one of our first topics in 3rd grade science class is plants. We examine the parts of a plant -- roots, stem, and leaves. We investigate the four things that all plants need -- air, water, sunlight, and soil. We explore the process of photosynthesis and discuss the fact that plants are producers and can make their own food, whereas animals are consumers and cannot make their own food. This always leads to an argument, because the kids insist that they can make their own food. "I made Spaghetti-Os for dinner last night!"
We also take a look back at where plants come from. We study the parts of a seed, the process of germination, and the details of sprouting. To more fully understand how this works, we do a little experiment with lima beans.
I put two or three lima beans in a Ziploc bag along with a wet paper towel. I then seal the bag and tape it to the classroom window so it can get sunlight. Over the next few weeks, the class observes the seeds as they split open, the green seedling begins to poke out, roots and leaves began to appear, and the seed transforms into a young plant.
At least, that's what should happen during those weeks. Unfortunately, this has never been the case in any of the five years that I've taped those darn seed bags to my windows. Instead, the lima beans tend to crack, shrivel up, and/or blacken. The closest thing I've ever seen to a sprout is a speck of green that died about three days later.
The other science teachers don't seem to have the same problem. I've looked at their baggies and wondered if we needed to worry about giants climbing down their beanstalks.
I haven't been able to figure out why my seeds won't sprout. It might be that I'm not using enough water on the paper towel. It might be that I'm using too much water on the paper towel. It might be that what I think are lima beans are actually white rubber erasers.
I think the big problem though, is the amount of sunlight the seeds are getting. My classroom is on the sunny side of the school, so I've often wondered if my seeds are getting flash fried. I usually have to keep the blinds down to keep the sun out of the kids’ eyes. So that's probably not a good thing for growing seeds.
Whatever the reason, I feel kind of bad for my kids. Year after year, they get a raw deal when it comes to scientific observation.
Maybe next year, we'll just give up on sprouting seeds and instead explore how Spaghetti-Os are made.
John Pearson is a third-grade math and science teacher in Dallas, Texas. He has degrees in mechanical engineering from Duke University and Texas A&M, so most consider his math abilities adequate enough to teach nine-year olds. He is also the author of Learn Me Good (Lulu, 2006), a funny, fictionalized account of his first year in education. Read more at www.learnmegood.com