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Author(s): Nancy Moreno, PhD, Barbara Tharp, MS, Deanne Erdmann, MS, Sonia Rahmati Clayton, PhD, and James Denk, MA.

Different Strains, Different Effects

Session 1: Getting Started

1. Ask students to share what they already have learned about where microbes might live and grow. Follow by asking, Do you think there are any microbes in this room? Where might they be? List students’ ideas on the board or overhead. 

2. Follow by asking, How could we find out if any microbes are present in these places? Encourage students to share their ideas, reminding them of the activity in which they observed bacteria growing in yogurt. If not mentioned by students, suggest that the class could collect samples from different places, provide opportunities for microbes from the samples to develop, and observe the results. 

3. Have each group of students select four places (or more, depending on the number of Petri dishes available) that they would like to test for the presence of microbes. Possibilities include the floor, a doorknob, unwashed hands, etc. 

4. Have each group create a table with two columns: “Location Sampled” and “Predicted Results.” Students should record information on this chart as they collect samples. For example, a group might predict that a sample from the doorknob will have more microbes than a sample from the surface of the door. 

Funded by the following grant(s)

Science Education Partnership Award, NIH

Grant Number: 5R25RR018605