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Saturday, January 17, 2015

Weekly Science Experiment #2

Thank you to everyone who offered support and encouragement after I reported on the failure of our first weekly science experiment.  I wasn't overly discouraged, but a few kind words are always appreciated.  We persevered, and this week our experiment was much more successful.

For week number two our experiment grew out of Ian's health curriculum.  The lesson was on "Touch Contamination" - which is basically germs being passed from person to person indirectly via things like doorknobs and other dirty surfaces.  We started by labeling two plastic bags - one with "washed" and one with "unwashed". 
 Then I thoroughly washed my hands, carefully removed a slice of bread from the bag and slid it into the bag marked "washed" as quickly as possible.  I also added two tablespoons of water and sealed the bag.  This piece of bread was meant to illustrate that clean hands do not spread germs.  Then I took out a second piece of bread and began to rub it on all the places where "touch contamination" is likely to occur - several doorknobs, a commonly touched windowsill, the buttons on the microwave and even the garbage can for good measure.  Then that slice of bread went inside the bag marked "unwashed" with two tablespoons of water.  
 Three days later we examined the bags.  The bread in the "washed" bag was slightly soggy, but had no noticeable changes.  The bread in the "unwashed" bag had specks of black mold and patches of white fuzz all over it (although it is not easy to see in the photo).
The kids were all rather grossed out by the mold and when I reminded them that the mold came from things the bread had touched that they also touch there was a stampede to the bathroom to wash their hands.  Yep, voluntary hand-washing by an 8-, 6-, and 4-year-old!  That's what I call a successful science experiment!
 Happy hand-washing, everyone!

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