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Why Do Pennies Turn Brown?
How to Clean Pennies
We filled some cups with different things in or kitchen to see which one would get our dirty pennies the cleanest. I had my kids each take a guess at which thing would get the pennies the cleanest. They were way off, so it was fun to see which really did get them clean. We left them in for 5 minutes then wiped them clean with paper towels.
Substances We Tested for Cleaning Pennies
We took them out and wiped each one off on a paper towel.
Ketchup was the clear winners for our pennies, with soy sauce next, maybe with a little more time they would have gotten a little bit cleaner.
This is a fun experiment to try with younger kids! My kids of all ages were interested in the results, though. So if you want to do it with older kids, just go deeper with the science!
Use my Scientific Method Worksheets to extend this!