Experiments

Today I judged at a middle school science fair - all the 8th graders are required to put together a science fair project using the scientific method and I was most struck by the incredible difference between the best and the worst presenters I judged. Some of the kids had obviously put thought and effort into their projects and some kids just barely showed up. Note it is not okay to tell the judge that you had forgotten about it until Saturday. And if your teacher spends the time to edit our research report, please make the changes and print out a new copy. In the middle of the pack were the students who had tried but I'm not sure really understand what it means to make a hypothesis and test it. For example, one of the girls wanted to test which candy dissolved the fastest - skittles, M&Ms, or lifesavers. A good start. So she put the skittles in sprite, the M&Ms in gatorade, and the lifesavers in water. She recorded the times and carefully graphed the results. I tried to gently explain the concept of a control and that really it's best only to change one variable at a time but it didn't seem to be sinking in. A select group of kids actually get matched up with a mentor at MGH and are able to do their experiment in a lab there. These kids had experiements like "How does acid range change soil?" and "How do you determine the density of carbon dioxide?" Really a different league. One of the girls looked me straight in the, introduced herself, shook my hand and launched in to a detailed explanation of her project. I was impressed. One of the boys forgot to bring his results so his poster was blank in the middle and he couldn't remember the specifics enough to tell me what the final conclusion was. I was not so impressed.

In the car on the way home I started explaining to the boys the basics of the scientific method. Start by asking a question, then make a hypothesis. "What's a hypothesis?" asked Mr. 4. "It's a guess." Mr. 6 jumped in before I could answer. I guess they'd already talked a bit about it in science - have I mentioned how much I love our school? We talked a bit about controls (I am determined that my kids will not undertake about candy experiment) and then the boys excitedly planned their own experiment. Mr. 4 wanted to see if salt made ice dissolve faster - seriously, I did not suggest this. Mr. 6 decided they should try other things to so the experiement became which of salt, sugar, and soap makes ice dissolve faster. They decided to use plain ice as a control (hurray, I'm not talking to myself after all). Their hypothesis was that salt would be the fastest. We came how and set it up.

It took a while but sure enough salt was the clear winner. Adding soap actually means the ice dissolves slower than plain ice which was a bit surprising to me but makes sense. How can you not love science?