By Rachelle Kean, a teacher and writer
Science, Math, Health, Fitness
Three class periods
10 – 12 (adaptable for a younger audience)
- understand the ways in which nutritional food labels are read and used on common foods
- determine the number of calories in a peanut (or the amount of fat in potato chips) so that comparisons to other foods can be made
- understand the detrimental effects of fats on the body and their relationship to heart disease, diabetes, and obesity
- increase awareness of healthy food choices for themselves and their classmates by designing and conducting a scientific experiment using observational skills and data analysis
Few will disagree that fast foods are a staple in the diets of many Americans. Even our nation’s schools feature vending machines full of foods that are high in calories, short on nutrition, and all too easy to buy. With busy lifestyles and complicated schedules, what are the long term effects of a diet high in saturated fats? What about all the “good carbs” and “bad carbs” we have been hearing so much about?
In this three part lesson, students will examine nutrition labels for caloric intake using various snack foods. Then, they will determine the number of calories in a food item. Finally, they will conduct a research project in which they examine the food choices of their classmates.
Part I: Pre-lesson Activity
- Separate students into two groups. Give one group the story “Fast Food Nation” and the second group “Fighting Fat.” Students should record the main points of the article in a notebook or journal and prepare a brief synopsis for the class. A brief debate is a great way to get them interested. Some possible debate topics include –
- Should “characters” be used for advertising when the target audience is often very young?
- Should schools limit or eliminate access to vending machines and soda machines in schools? Why or why not?
- Is it a school’s responsibility to notify parents and/or students when a student is seriously overweight considering all of the ill health effects?
- What are some ways that American life leads to obesity and what can be done about it?
- Should gym class be made harder? Why or why not? Do you think students would approve?
- Should grocery stores and convenience stores make junk food less visible? And should the prices be higher for high fat/low nutrition foods?
- Should nutrition content of school lunches be made easily available to students who want to make better choices?
- What impact do you think food labels have on the choices Americans make with their foods? Do you think they should have warning labels similar to the Surgeon General’s warning on cigarettes?
- Using the stories and the Web, students should define the following:
- Trans fats
- %DV (percent daily value)
Part II: Nutrition Labels
- Many people do not know how to read a nutrition label properly. Although nutrition labels are in place to help the consumer know exactly what is in their foods, many simply don’t understand the caloric requirements of the human body as it relates to nutrition labels. Go to the U.S. Food and Drug Administration Web site at http://www.cfsan.fda.gov/~dms/foodlab.html to find more information and sample nutrition labels.
- Divide the class into groups of 2-4 students. Distribute several boxes or small bags of snack foods to the students. Ask students to get out 1 serving of the food. They should not look at the nutrition label, but are to take a good guess at what they would consider one serving. Then, have each student measure the actual amount of the snack that they have withdrawn and record this in a journal.
- Investigate the parts of the food label with the students. In particular, demonstrate the number of calories in the food items, serving size, percent daily value, and the 2000-2500 calorie diet on which the label is designed. Then have students calculate the actual amount of fat and calories in their sample size. Discuss their reactions. They should clearly see that the serving sizes are often very low. In addition, discuss the caloric intake needs of a teenager or complete a calorie calculator.
Part III: Calories and Fat
- This section has two alternative labs based on material availability. One is from the Wyoming Energy Curriculum and needs simpler materials. It is aimed at younger students. The second is a higher level chemistry laboratory aimed at older students in a true chemistry lab.
- Print the student and teacher materials for the lab of your choice. Complete the labs and discuss the amount of fat and calories in average foods. Concentrate on student reactions to the amount of fat and calories in those foods.
Part IV: School Surveys
- Students should now have a great idea of how fat and calories play a role in their lives. But what about their classmates? Students will put together a “secret survey” in which they will watch their classmates at lunch and determine a nutrition index of the foods that are chosen.
- Divide the class into groups of 2-3 students. Obtain a lunch menu for the week and distribute copies to each student. Using colored pencils or markers, students will determine a scale rating of 1-5 for the food choices. 1 will be a very high fat, high calorie, low nutrition food item, while a 5 will be a healthy whole food like apples, real chicken breasts, and so on. They should make the key and list example foods at each level. For instance, broccoli, although a good food source, once loaded with cheese or butter can go lower on the scale. Other foods such as snack cakes would be a 1.
- Students must then make a data table in which to record their experimental results or use the worksheet provided. They will spend one day in the cafeteria watching the foods that others eat. They will record this in their data table. Together, they will determine the ratings of the foods that are chosen.
- For an even greater challenge, have students design their own observational experiments. For instance, how much money is spent on average on the snack machines each day? How many students choose apples over apple pies? And so on. It is a great way to get students to design their own experiments and record their results. A complete lab write-up would be appropriate for older students to turn in.
- Watch the movie “Super Size Me” and have students comment on the facts presented in the film.
- Research and compare the marketing budgets of several large fast food or soft drink companies and ask students to debate the topic.
- Have students create a comparative timeline of the advent of fast food popularity and the growing trends in obesity.