Bring to class several samples of moldy food such as an orange with green or blue mold covering part of it, an apple with a brown spot, a sweet or white potato with black mold on it, or a carrot with a soft, moldy area. Scrape some mold from each sample onto healthy specimens of the same kind.

Put the healthy specimens in sealed jars. Next, jab a sterilized needle or stiff wire into the moldy portion of one sample, then pierce the skin of healthy samples of different
fruits and vegetables. Repeat this for each of the moldy samples, sterilizing the needle each time.

Put all the inoculated, healthy specimens in sealed jars. Compare the results after several days.

After examining the healthy specimens that had mold scraped onto them, discuss how fruits and vegetables are structured to resist infections.

You will also realize that certain molds grow only on certain foods.

Does this tell you anything else?