Hamsters, Eggshells and Robots! Oh my! — the 3rd Grade Science Fair

When the gymnasium doors opened, the entire third grade stood proudly in front of their science fair experiments. This is an annual ritual at AVS starting in first grade. Every year the experiments get a little bit more complex, and every year, the students conduct their explorations more independently.

Here are just a few questions asked by a random sampling of kids at the science fair. They reflect the diverse curiosity in the third grade explorations.

  • Will a robot draw a circle better with the propeller in the center or at the edge?

  • Which plant (of those chosen) has the most seeds? Why is that important?

  • Will a hamster navigate a maze faster if it can smell the treat at the end?

  • How long does it take an eggshell to melt in hydrochloric acid, in hydrogen peroxide or in vinegar?

  • Do treads or wheels provide more traction on a robot navigating obstacles?

  • How many pennies and nickels does it take to make 1 Volt of electricity?

The young scientists learn to ask a testable question, something that can be measured, not “I think the worm likes to eat banana peel.” Then they set up an experiment with controlled variables, dependent variables and independent variables. They learn how to test, record and chart their results. They draw conclusions to see if their hypotheses were accurate. Sometimes they were wrong, and that’s part of the learning process.

Alejandra’s experiment, “Bot Drawing-ology,” tested whether a robot with a centered propeller would draw a neater circle than if the propeller was placed off-center. She hypothesized that the bot needed to be centered to draw a good circle. And that’s what happened: the robot with the propeller placed in the center of the top of a plastic cup drew a neat circle on paper. It drew unruly dots with the propeller placed off to the side. Alejandra proved her hypothesis.

In “The Egg Shell Meltdown,” Anya showed that hydrochloric acid dissolved an eggshell in 30 minutes. Vinegar took 13 hours, and hydrogen peroxide did not dissolve the eggshell at all. “I used my chicken’s eggs, my Goldie’s egg, the brown ones,” she said. Her conclusion? If you want to dissolve an eggshell, never use hydrogen peroxide. Helen’s project, Maze Runner, asked if her 1-year-old dwarf hamster, Frijoles, would find the treat – a yogurt drop — at end of the maze faster when he could smell it. He found his treat in 42 seconds, when there were no opposing smells around the maze. When the smell of the treat was masked by swabbing the maze with alcohol wipes, Frijoles took 2 minutes and 52 seconds to get through the maze. Her conclusion? “My hamster depends on his sense of smell quite a bit.” The yogurt drops also come in handy when you lose your hamster! “A Very Seedy Situation” tested which fruit – a pomegranate, a watermelon, a pepper, a cantaloupe, or an orange – would have the most seeds. Charlotte thought a watermelon would have the most seeds because it is big, and she was right! Her pomegranate had 515 seeds; the pepper had 59 seeds; the orange had 3 seeds; the cantaloupe had 771 seeds, and the watermelon had 816 seeds. She learned two fun facts not related to her testable question, “A seedless watermelon is not seedless, because it (hers) had 816 seeds,” and “Pomegranate seeds are very yummy on tacos!” In his experiment, “Robot Going Over Obstacles,” Johan wondered if a robot vehicle with treads would go farther on a knobbly, grass rug than one with wheels would go. He programmed the vehicles to go for 15 rotations and watched. The robot with treads traveled about 85 inches versus an average of 75 inches for the robot with wheels. It’s what he thought would happen. Johan’s take-away: “If you are four-wheel driving, or if you are driving in the hills, you might want treads, like chains, for traction.” Owen’s exploration, “Have We Found Cheaper Electricity Bills?” made a simple battery using a penny, a wet paper towel soaked in a vinegar and salt solution, a nickel and tin foil in patterned stacks. He thought it would take seven repeats to yield 1Volt of electricity, but his experiment showed it would take only 3 repeats. Owen concluded, “My research tells us that it might be cheaper to make your energy out of pennies and nickels than paying bills.” But why do a science fair every year; what’s the point? Aren’t we living in an age where kids should be making extrapolations from hard data and charting it all? Here’s how Ed Walters, head of AVS, thinks about this question:

A science fair requires students to demonstrate their knowledge through a project and oral presentation, not just by answering questions on a test. The design supports a methodology that has many applications – the structure of how to solve a problem? It encourages students to struggle and turn to one another for help. It engenders resiliency, organization, data collection and analysis, and the idea that failure is okay because it provides the opportunity for us to look at the problem in a new an enlightened way.

And, this parent learned from Max, “If you want to make a really big explosion, you need to use mint Mentos, not fruit ones.”

#Science #StudentWork


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