Food experiments can also teach students about food safety.
The steps of the scientific method can be too abstract for fifth-graders to grasp without hands-on practice. Using simple readily available foods makes the concepts of scientific investigation concrete and accessible, and rotting food has just the right "ick" factor for fifth grade. When conducting experiments in a classroom setting, an adult should cut up foods when required. At home, your fifth-grader can handle such tasks with close adult supervision. Before beginning any science experiment, review appropriate safety procedures.
Light
This project compares the speed of decomposition of foods that are kept in light versus those kept in darkness. Slice an apple and a zucchini into small pieces. Divide the slices of apple between two small polystyrene foam plates and do the same with the zucchini. Label the plates with the name of the food and the date. Place one plate of apple slices and one plate of zucchini slices near a window or in another place with lots of light. Turn a cardboard box upside down and cover the other plates of food. Check the plates each day for about three weeks, making detailed notes about the look and smell of the foods.
Yeast
Compare the decomposition of a banana treated with yeast to that of a plain banana. Cut four 1-inch slices from a banana. Using clear plastic zipper bags, place two slices in one bag and two in the other. Add 1 teaspoon of yeast to one bag, making sure the yeast touches the banana. Seal the bags and label them with the date. Be sure to note which bag contains the yeast. Observe the bags for one week, making careful notes about how the banana slices in each bag look.
Food Storage
Determine what method of food storage causes foods to rot the quickest. Slice two apples and divide the slices into four groups. Place one group of slices into a plastic container with a lid and one group into a plastic zipper bag. Wrap one group of slices in aluminum foil and the last in plastic wrap. Put all four samples into the refrigerator. Examine the apple slices each day for two weeks, recording details about how they look and smell.
Preservatives
Add agents to blackberries to determine which preserves the berries the longest. Place two berries in hydrogen peroxide and two in an algicide used to prevent growth of algae in pools. Allow the berries to soak for about 15 minutes. Use household rubber gloves to handle the berries soaked in algicide. Roll two berries in salt and two in sugar. Set two berries aside to use as a control. Make a chart with each agent listed across the top and the days down the side. Observe the berries each day for 20 days, making notes about the appearance of mold and any other differences among the five samples.
Tags: notes about, apple slices, group slices, into plastic, look smell