Growing and studying bread molds with third graders

We asked microbiologist Chris Odt to explain how she worked with third graders in Mrs. Tormey's class to grow and study mold. She sent us floppy disks with images of their mold and a letter that explained:

"First we grew our molds on:

• a leading brand of white bread from the grocery store
• homemade bread machine bread; and
• flour tortillias

"The tortillas didn't grow anything, after 4 weeks. I assume because of the 'compactness' of the tortillas. The store-bought bread worked the best, but both breads, after 2 weeks, were really, really gross. (The kids loved it.)

"All we did was to put bread slices in plastic zip-seal bags, with 5-10 drops of water, and then seal them up. Their teacher then hung the bags up on a 'clothesline' in the classroom so they could be viewed easily, 2 weeks later.

"Then I went back to her class, supplied with 50 agar petri plates, filled with Malt Agar, which is used for isolating yeasts and molds in foods. I taught the kids how to make 'aseptic transfers' with sterile, plastic inoculating loops. It was a mess, but they loved it.

"I also left the class with some agar petri plates they could put anywhere at school, like the playground and music room to get samples. They just left the plate open during their music class, and during recess, for example.