A Lemon of a Science Fair Project


When life hands you lemons, make… batteries!

HapaPapa and I are the only couple in Silicon Valley that does not include at least one engineer. It’s almost comical. Our DVD player is ten years old. We own a VCR. And when the computers blue-screen, we just sit there and hit the “On” button, hoping it will come back to life. But there are times when our technical ineptitude is no laughing matter. Last weekend was one of those times.

It’s the Science Fair!

It’s not that I don’t like science. I’m just emotionally scarred by it. For my first year and a-half of college, I took the requisite Asian premed courses.  Unfortunately, those organic chemistry classes did not go well. Did you notice, there’s no M.D. after my name? Fortunately (or even more unfortunately), that experience gave me enough of a taste of the scientific method to make me ever so confident in my ability to teach my fourth grader a thing or two.

I appointed myself the Science Fair Parent.

I come from a long line of engineers and scientists. My own PhD father was a whiz at science projects. When I was in fourth grade, I wanted to make a volcano. You know… make a paper mache mountain with a crater on top. Fill it up with baking soda and food coloring. Pour in vinegar and watch the red foam mess up your kitchen.

But no. Volcanoes don’t really test any scientific theories. Everybody knows what happens when you mix baking soda and vinegar. My dad insisted that we make an alcohol lamp.

lemon battery science fair

I would let my fourth grader choose his own Science Fair project.

Big Brother came up with the idea of testing lemon batteries against store bought batteries. Great idea! Except we waited until the weekend before the due date, and who knows how long those batteries might last. We did some internet research and found out the lemons really don’t produce enough electricity to power much anyway. So we decided to change our hypothesis.

How many lemons does it take to make as much power as one store-bought battery?

My job would be to buy a Costco size bag of lemons. And take the photos. HapaPapa would buy a voltmeter (at Radio Shack, not Home Depot!). Big Brother’s job was to do everything else. Of course, he was really excited to use a knife — a sharp one! — to cut slits for the pennies. Pushing sharp nails into the other side of the lemons was almost as much fun.

So what exactly is the mom supposed to do?

Take pictures, of course. That’s one area where I could legitimately overachieve without taking away learning opportunities from my child. Except the batteries in my good camera were drained, and Big Brother did not want to wait a few hours for them to charge up. Not when there were sharp knives and electricity involved. So, point-and-shoot it was.

The mom can also trouble shoot when the lemon batteries — even a circuit of four — fail to power anything, even though they generate the more volts than a D battery. Moms can google really well, too. We found a great tutorial that explained that while lemons can create a decent voltage, they lack amps. (Read more about lemon batteries on hilaroad.)

Voila! That’s our conclusion!

Now all we had to do was type it up and make a nice display. Big Brother and I worked together to find cool fonts for the board. I even let him choose Frankenstein style lettering, although I did convince him that neon green was a better color choice than blue.

Sometimes you just have to remove yourself from the situation.

With everything printed up, he grabbed a fat purple glue stick and started pasting construction paper willy-nilly all over the board.

“Oh those cracks? We can cut up little pieces of paper and cover them up when we’re done.”

Instead of arguing, I went to the other room to check Facebook. When I came back, photos were glued randomly around the board, and page two of the conclusion was pasted above page one. Okay, I made him fix that one.

lemon battery science fair display



Well, what do you think?

It looks like it was made by… a fourth grader. And I couldn’t be prouder.




Leave a Reply

Your email address will not be published. Required fields are marked *