To learn more about how different materials decompose (break down) over time, set up a simple experiment. This works best outside since decomposing materials can get a little stinky and attract critters.
Collect two of the same thing from each of the following waste categories:
Place one of each kind of waste (ex. apple, oak leaf, paper towel and sandwich bag), in a plastic container (old yogurt containers work great) and the rest in a paper bag. Cut off the paper bag so the top is just a little taller than what is inside it.
Decide where you want to put your waste samples: buried in the ground, buried in a compost pile, sitting on the ground, sitting on pavement, sitting on a compost pile, in the sun or shade, etc. The key is to put both samples in the same type of environment, so that variable in your experiment is controlled. The variable you are testing is whether the waste is enclosed or open, so you want to control all other variables in the experiment.
Make a plan for observing your bundles of waste on a regular schedule, and always observe both bundles at the same time. Think about how you want to record your observations. You might make a table similar to this one, with enough room to write observations in each cell:
There is no right or wrong way to schedule your observations and record them. The important thing is to be consistent! Happy decomposition.