Yeast and Carbon Dioxide Experiment

• Yeast is a common type of fungus commonly used in baking bread. This experiment will measure the amount of carbon dioxide that is released as yeast grows in different liquids. You'll need equal amounts of soda, flat soda and water. Pour the liquids into identical soda bottles and label them. (Yeast can eat the coloring in soda, so this is important to tell them apart.) Add 1 tsp. active dry yeast to each bottle, put the lids on and shake. Remove the lids and place a balloon over the mouth of each bottle. Make sure the balloons fit tightly. Place the bottles in a warm area away from sunlight. Each day, measure the diameter of the balloons by wrapping a string around them at their widest point and then measure the string. Record the info. Calculate the average growth of the three balloons (add them together and divide by three), as well as the growth of each individual balloon. Create a graph of the averages to show the growth. Note which bottles gave off the most C02.
  
  

Effects of Temperature on Growing Fungi

• This experiment examines how temperature affects the growth of fungi. Cut three 3-inch-square pieces of bread and add 1 g brown sugar and 1 tsp. water to each piece. Apply the sugar and water evenly. Place the samples in plastic sandwich bags. Place one bag under a lamp, one at room temperature and one in the refrigerator. Once a week over a four-week period take a picture of the samples and record your findings in a journal. Note which samples produced the most fungus. To ensure the reliability of the results, repeat the experiment again using same conditions and variables.
  
  

Impact of Fertilizer on Mushroom Growth

• To conduct this experiment you will need two mushroom-growing kits. Divide each kit in half so you have four blocks. Separate the blocks from each kit with a waterproof barrier of cardboard wrapped in aluminum foil. Label the first two blocks "A" and the second two blocks "B." The first half in each block will be fed only water as a control. The second halves in each block will each be fed a different type of fertilizer. Fish emulsion (available at most nurseries and garden centers) and cow manure are two good choices. To create the manure fertilizers, place 3 tbsp. manure in 1 qt. water; mix and then strain. Place the fertilizers in spray bottles. Place the grow kits near a window so they all receive the same amount of light. Wait until the mushrooms are about 2 inches tall before feeding them, then begin twice-daily feedings. Feed the first half in each kit only water. Spray the second half in the first kit with the fish emulsion and the second half in the second kit with the manure mixture. Shake your spray bottles well before feeding. Measure the mushrooms daily and record your results. After harvest, weigh the different groups of mushrooms and record the results. Take pictures and place your findings on a chart or graph. Which fertilizer, if any, provided the best results?
  
  

Effect of Bleach on Mold

• Bleach has always been known as an effective way to kill mold. But how concentrated should it be? Will small amounts do the trick? This experiment is designed to find out. Cut some bread in six equal-size pieces and prepare six petri dishes with agar. Place one piece of bread on the petri dishes. Prepare five bleach solutions of 1, 2, 5, 10 and 20 percent. You will also use plain water. Place the water and the five bleach solutions in spray bottles. Twice a week, spray each dish with the water and the beach solutions, making sure you label which dish is getting which solution. Keep the bread moist. Over a 10- to 20-day period, observe the mold growth and record the results. Create a chart that illustrates your findings.