What is the Importance of Hygiene?
I obtained Petri dishes from a local high school lab and took samples from various sources to show the importance of cleanliness.
Samples were taken from: unwashed versus washed hands, new vs. old toothbrushes, and we had someone cough directly onto a Petri dish vs. having their mouth covered. The Petri dishes were grown out for 3 days and the number of bacteria colonies were counted.
As hypothesized, using good hygiene (the washed hands, new toothbrushes, and covered mouth samples) produced fewer bacterial colonies.
As the actual bacterial samples could not be displayed with the poster board, we took large photographs of the results and placed those in front of the poster board for examination.
This was a fourth grade level project.Barry's Response
- Pretty advanced for fourth grade, Leah. Congratulations.
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this site for more information now.