As a final investigation, I thought it would be instructive (and fun!) to test foods of our own choosing, instead of basing everything on the samples provided to us in the science kit. So I asked everyone to bring in two food samples: one food that they like to eat at home, either a favorite food or a family-related dish, and one food that they like to eat that is a "junk food" – candy, snacks, etc.
The first thing we did was use the iPads and the laptops to do research online on each of the samples to record nutrition information about them. This will help as we do an investigation into how they break down during digestion.
Food Project Nutrition Worksheet
I set up our classroom with stations so that everyone could test their two foods. We put the foods through most of the stages of digestion: We "chewed" the food using toothpicks or a mortar and pestle; we added amylase to simulate chemical digestion in the mouth; we added gastric juices to simulate digestion in the stomach; and we placed the samples in a hot water bath set at body temperature for an hour or more to simulate the time spent in the stomach. We didn't get to add lipase or simulate any digestion past the stomach, but I did add a basic solution to everyone's samples at the end to neutralize the acidity to make them safe to handle and dispose. We used our indicators for sugar and starch at each step of the process to measure any changes in the food, and noted any visual observations we could make.
In addition to performing this three-investigations-in-one activity, I added in a final project step by proposing a scenario: You are a food scientist who works for Seattle Public Schools. Your boss (someone who is not a scientist) has given you two food samples and asked you to do research on them to determine whether they are appropriate to serve in the school lunch program. You use your research to support your claim about each food. Since your boss doesn't understand the science, you will also need to include a bit of a story about each food, explaining what happens to it during digestion in each step: in the mouth, in the stomach, and in the small intestine. There are other requirements for your report, which are detailed on the back side of the investigation worksheet. But, it is not a long and involved project, and could be completed in about two pages of work. However, to complete all of the items on the checklist, it might take a bit more than two pages.
In addition to the checklist, we will be looking for you to use at least three vocabulary words in your report. Again, it would be hard to complete the checklist without using at least three vocab words from the unit! Since this will be graded as if it were a quiz, we want to stress the importance of using evidence to support your claims. It was one of the main learning goals for this unit!
Please let us know if you have any questions, and we hope you have some fun with the project!
