Dr. Brian Mitchell from Northwestern University’s Feinberg School of Medicine came to talk to Ms. Darley’s 4/5 class about bacteria. After learning about the structure of bacteria, “good” vs. harmful types, and the presence of bacteria throughout Earth’s history, kids set up experiments. They made samples to contrast ‘clean’ and ‘dirty’ hands and then also tested the ‘dirty’ hands in a solution with an antibacterial agent to see if bacteria would still grow. We also tested for a few other variables: cold vs. hot and how bacteria would grow with a saliva sample over the skin samples.
The kids also looked at frog embryos through a microscope. This is the beginning of the ecosystems unit in 4th grade. Dr. Mitchell’s visit extended the students’ thinking about bacteria habitats beyond what they would ordinarily do with this unit.