Over on Facebook I follow some groups who find provocative topics, and today’s “science fair” post was so over the top that I had to share it here.
Here’s the original post. Now the accompanying text about microwaves is whacky enough on its own (and well worth reading), but my primary interest is with the experiment. This exemplifies why there are basic rules for doing science.
This starts out okay – identical pots, the same type of media (I assume), similar sized plants – but then things go downhill:
1) Replicates are important. There is one treatment and one control, meaning that it’s impossible to run any kind of statistical analysis. Ideally between 10-20 replicates of the control and the experimental treatment are used in this kind of experiment. That’s 20-40 plants total.
2) Variable control is important. Plants in a windowsill are subject to light and temperature gradients. That makes analysis more complicated unless one has an extremely long windowsill so that all plants are treated uniformly. And then our researcher prunes the tops of the plants – yet another variable.
3) Consistency between treatments is important. It appears that the pot on the left is wetter than the one on the right – the media is darker. If it’s not draining well – for whatever reason – then you’ll have a hypoxic root environment. Plants don’t like that.
4) Objectivity is important. It’s difficult (impossible, really) for any researcher to be completely objective. Ideally, the pots would have been watered by another person and then labelled in such a way that the person recording the data would have no clue which was which.
I think it’s really important to get kids excited about science. But it’s just as important giving them guidelines about doing science in a way that advances their own understanding about how the world works. Otherwise, it’s just more fodder for the aluminum hat crowd.