It’s that time of year again: March. Science Fair countdown.
I am a fan of the Science Fair. I have served as a judge for multiple science fairs at schools in the area. I think the science fair can be a great way to teach children several important scientific principles that can’t be replaced by reading books on science (even living books), or by reading about famous scientists and what they discovered. Both of those are important parts of elementary school science, but they don’t teach children what science is.Science is asking a question, designing an experiment, recording data, and drawing conclusions from the data.
Science is NOT finding a theory you like, trying to fit what we see around us into that theory, and defending the theory. I have unwittingly demonstrating this very bad process to my children in trying to carry out the science experiments in kids’ science books.
It goes like this. (This is an actual transcript from a science experiment we did in our own kitchen.)
Mom: [seeing that she wrote "science experiment" in her planner for today] Kids, today we’re going to learn about acids and bases. Acids blah blah blah blah… and bases blah blah blah blah… so pour this chemical in that bowl and we’ll see what happens.
[Kid B spills half of chemical on counter but manages to splash a little into a bowl which emits a foul odor and fails to do what the book says it will.]
Kid A: Wow! Look at that color!
Kid B: That smells terrible!
Kid C: What happens if we put MORE in?
Mom: [frantically reading ahead from book and moving bottle of chemicals out of reach of Kid C] Well, that wasn’t supposed to happen! What we were supposed to see was blah blah blah blah…
[kids go to write in notebooks what was supposed to happen. Mom grumbles and dumps the chemicals before the whole house reeks of rotten eggs]
What my kids learned from this particular “experiment” was that we don’t pay attention to what happened in the experiment. No, we pay attention to what the book said was supposed to happen.
But experimental science, when done right, is really asking a question which leads to more questions. When I have an unexpected result, I should be asking “Why did that happen?” and observing the result I DID get, and then asking why that might have happened.
Instead of squashing my kids’ questions and observations, I should have been marveling with them at the horrible smell and wild color. Sometimes a “failed” experiment will lead to the repeating same experiment with better technique. Sometimes it will change the next step of the experiment altogether.
So what does that look like for young scientists? Well, it looks different based on the question that interests them. But here are a few tips that have helped us get from “er…” to “I get it!” I’ll use one of Jonah’s experiments to illustrate what I mean.
1. Start with a yes/no or true/false question, not with a procedure.
Often a child will have read or seen an experiment in the past, and they want to copy it. That’s okay as long as they have their own question in mind. Asking a question leads to a hypothesis. (The hypothesis is just the answer to the question.) Without a question, your experiment is really just play.
Initially, Jonah wanted to prove that more sugar made a better cookie. His question: Does more sugar make a tastier cookie? His hypothesis: YES.
2. Control your variables.
Jonah took a standard sugar cookie recipe and altered it. He made one batch of cookies with 1/8 the amount of sugar in the recipe, one batch with 1/4, one batch with 1/2, one batch as written, one batch with double, and one batch with triple the sugar. (Pro: this experiment involved a lot of math. Con: this experiment involved a lot of sugar.)
Here is Jonah weighing his ingredients in grams to make the recipe as standard as possible.
Other than the sugar, the rest of the variables remained the same. Same flour, same butter, same vanilla, same baking soda, same eggs. The cookies were labeled by number (so the tasters wouldn’t know which recipe they were tasting) and presented to each taster in a random order, so that they wouldn’t be tasting the same cookie as their neighbor at the same time (to eliminate peer pressure as a variable).
However, changing the sugar had the unintended result of altering the texture of the cookie, so that the
victim cookie tester then was judging the cookie based not only on taste, but also on texture. This was a failure to control all our variables.
Here is Moriah’s bacterial culture experiment, which she documented in photos.
3. Observe closely. Keep good records.
For Jonah’s experiment, he kept a copy of each recipe, took photos of each batch cookie, and gave each taster a piece of paper on which to rank the cookies in order of taste. All three methods of record-keeping worked well for this experiment. Let the data guide how you record it, but get it onto paper (or film).
4. Discuss the data you have, not the data you didn’t get.
Jonah really expected everyone would LOVE the sweetest sugar cookies, but that wasn’t how it played out. What could he conclude from that? Well, 80% of his testers preferred cookies with LESS sugar than called for in the recipe. He wanted to draw all sorts of other conclusions about how age affected cookie preference, but he didn’t have enough data.
5. Make a conclusion in relation to your hypothesis.
Generally, your conclusion should be Yes, No, or We Need Further Experiments. Jonah’s conclusion was NO.
Making a conclusion that your data doesn’t support isn’t only wrong, but it’s foolish. All anyone has to do is repeat your experiment (which they can do, because you laid it all out there for them to repeat, right?) to see that your experiment (or your conclusions, at least) doesn’t hold water.
Following these steps not only will give you a good project– and by good I mean that you have done good science, NOT that you will necessarily “prove” anything– but it will teach your children how to read scientific literature. We need our children to be able to read critically. To understand when someone is using shoddy science to prove a point. They need to be able to see when there is a confounding variable (like the altered cookie texture). They need to be able to tell that a study’s data is incomplete, or that the data don’t support the conclusions drawn.
Helping your child do a project for the science fair is not about a blue ribbon at the end: it’s about learning how to think.
Here are links to my past posts (each with more detail than here) on helping your child prepare for a Science Fair: