What is this a picture of? This is a paper bag full of un-moldy bread. It’s a very sad thing, too. Here is the whole story.
A few weeks ago we were doing a germ unit in the second grade classroom I was working with. We wanted to do something with petri dishes so that the students could see that there really are germs on the things that we touch every day. However, petri dishes are expensive! I found lesson plans that had the students use slices of bread and plastic baggies instead, and it supposedly worked. So that is what my students got to do.
I was very careful with my choice of bread. I picked one that had no preservatives. Each student was given a slice of bread and a plastic baggie. On the baggie they wrote their name, and where they rubbed their bread. Then we spritzed each slice with water and sealed them in plastic baggies.
The students LOVED the project and couldn’t wait to see what would grow on the bread. Some of the students had rubbed their bread on desks, carpet, door handles, drinking fountains, etc. Since they weren’t allowed to get germs from the bathroom for this project, both their teacher and I rubbed pieces of bread on toilets to see what sorts of nasty things would grow.
The lesson plan said that the bread needed to be kept in a warm, dark place. We put them all in a brown paper sack and left it in the warmest part of the classroom. I even took the bag home over the weekends since the school’s heater is turned off and it is cold!
We anxiously awaited the growth of anything on the bread. We checked daily. 3 days passed. Nothing. 5 days. Nothing. 7 days. NOTHING!
At this point their teacher and I were talking about how anything that grew would thrill the students. Even if it was just mold they would love it. It couldn’t be long until they went moldy, right?
10 days. Still nothing. 14 days. Nothing. It has now been almost three weeks, and NOTHING has grown on the bread. Not even mold. The bread looks like you could take it right out of the bag and eat it (ick!) and it feels as soft as ever. So disappointing.
So the moral of the story is: If you don’t want your bread to mold, just rub it on the floor, the wall, or even the toilet. It seems to do the trick.


