Science Buddies: "Ask an Expert"

I'm planning on doing a tooth whitening experiment on hard boiled eggs (or their shells). My question is whether natural remedies for teeth whitening would work better than commercial brands. There are many different whitening toothpastes on the market as well as different natural remedies, such as activated charcoal and turmeric. How can I simplify this experiment? Use 1 natural remedy vs 1 commercial brand? Or test several brands against both natural? For the control, is it just a white egg without stain?I don't want it to get too complicated. Do I then decide on which type of stain (wine, soda, coffee) or narrow it down to one variable? Also, is it up to me to determine how long the stain sits on the egg shell before testing?
Thanks!

Hi Katie!

To simplify your experiment you could choose 1 type of stain and test in various ways. If you wanted a very simple test, you could do 1 natural remedy and 1 commercial brand like you mentioned. If you wanted a little bit more data you could select a couple commercial brands and a couple natural remedies to see which category removes the stain the best. On the other hand, you could have 1 commercial brand, 1 natural remedy and multiple variables (stains). As for the control, I believe you are right, that it would be without the stain. You can also choose how long the stain sits.

Hope this helps! Good luck on your project!