Classroom Activities
Classroom Activity # 1: "The New Healthy Eating Pyramid"
Objective: Students will examine "Dr. Walter Willett's "New Healthy Eating Pyramid." The teacher will lead the class in a discussion of each pyramid component. Students will then be introduced to the USDA's new food pyramid entitled "MyPyramid." The teacher will have students compare and contrast both charts. Students will identify the similarities, differences, strengths, and weaknesses of each. Students will be provided with a blank copy of both new pyramids and be asked to categorize foods according to their food groups. They will be asked how much of each category they should eat; they will share their results with the class. The teacher will direct the students to look over and read the USDA MyPyramid website for further information (see Student Resources.)
Classroom Activity # 2: "The Children's Activity Pyramid"
Objective: Students will use the "Children's Activity Pyramid" to generate a list of physical activities and exercises they can complete in the classroom, at recess, or at home. The teacher, along with the physical education teacher, will devise a list of 20-30 simple exercises that students can engage in on their own time, with minimal supervision. The teacher will instruct the students in each of the exercise that were developed. The students will get copies of each exercise. Websites have been provided with excellent links to this activity (See Teacher Resources.)
Classroom Activity # 3: "You Are What You Eat - Food Products vs. Whole Foods"
Objective: Students will learn how to differentiate "real whole-foods" from an "edible food like substances" using various test criteria set forth by Michael Pollan's book "In-defense of Food. An Eater's Manifesto." To compete this activity the teacher will need to have each of his or her students bring in 2-3 food items each, all must be non-perishable with parental permission. This gives the teacher flexibility in planning. Items should be in cans, boxes, and bags. Food items brought in should come from a variety of sources and should not be all "snack foods." The teacher will bring in "perishable items" for this lesson. Assemble all food items for day of instruction. Use chart paper to list Pollan's tips in a format all children can see. Have the children classify the items based upon the tips on the chart paper.
Classroom Activity # 4: "The Digestive System"
Objective: Students will explore the human digestive system by use an anatomically correct model, diagram, or "Smart board" interactive to identify each of the system's parts and its proper function in the digestion and metabolism of food. Students will use the anatomically correct model, diagram, or "Smart board" interactive to follow food's path from the mouth to the anus. Students will view a short "web-movie" on human digestion. Two formats and links have been provided. One is simpler animated and narrated version. The second is a brilliantly, computer-generated interactive that allows the students to drag and drop all the parts of the digestive system into place, only to be followed up by a CGI high quality movie that follows food through the body following an "inside" view that could only be provided by laparoscopes. (See Teacher Resources.)
Classroom Activity # 5: "Healthy Weight and Body Mass Index"
Objective: Students will calculate their weight and their body mass index (BMI). Note, do to the sensitive nature of body image, personal weight, and BMI; this activity needs to be completed in two parts. Before the activity, the teacher will set up "Personal Weight & BMI Station" in the classroom away from most students. In that station, the student will need a scale that measures weight and height (see your school nurse for this), a computer with Internet access, and a measuring tape. During the whole-class session, the teacher will make clear what weight and BMI are and identify how each one are calculated using a height/weight scale, ones age, measuring tape, and an online BMI Calculator. Teacher can use him or herself as a demonstration model or make one up. During individual center time, students will take their personal body measurements (height, weight, age) and use a children's online "BMI Calculator" to determine their personal BMI. The teacher can assist in calculation as needed. One strategy that may be applied at this stage is to invite the school nurse in to discuss individual BMI with each student. (See Teacher Resources.)
Classroom Activity # 6: "Calorie Counting"
Objective: The class will use a homemade calorimeter to determine the caloric content of various samples of fruits, vegetables, or other foodstuffs. In this lesson, students will start by looking at a variety of food labels and the information contained within. Students will discuss what a calorie is and how it is calculated. This lesson is a great demonstration lesson in which students act as "teacher assistances" while the experiment is going on. Due to the nature of the experiment, prior administrative approval is strongly advised. You will be generating heat and smoke and that in turn may interfere with the fire system in your building. The use of goggles is needed. Proper ventilation such as a portable hood is highly recommended, if not available outside set up might be best. The availability of a fire extinguisher is strongly suggested.
The complexity of the mathematics, construction, and analysis of results after burning make this lesson very appropriate for "gifted and talented" students. If you are leading the experiment, you will work through the complex mathematics with the class via an overhead, white board or the like. This activity is most appropriate at the upper elementary and middle school level. The "Burning Calories: How Much Energy is Stored in Different Types of Food?" link provided gives very detailed directions to successfully completing this lab experiment. (See Teacher Resources.) Examples of foods burned are given, however consider any food allergies of your children first. The worksheets provided in the sample lab can be used as a basis of a "class chart" your class can journal about after you have burned different items. This activity was originally developed by the University of Southern California's Biology Department in 2004.
Classroom Activity # 7: "Sugar, Sugar Everywhere"
Objective: Students will use a simple "Benedict's solution" to identify the simple sugar in various food samples. Benedict's solution is used to test for simple sugars, such as glucose. It is a clear blue solution of sodium and copper salts. In the presence of simple sugars, the blue solution changes color to green, yellow, and brick red, depending on the amount of sugar. Note: an adult must supervise this experiment. What you'll need: 1 bottle of Benedict's solution, assorted small pieces of food (cookies, crackers, bread, fruit), several glass test tubes, 1 heat source (burner, gas or electric), and tongs. What to do: Place a piece of food in each test tube and then pour 30 - 40 ml of Benedict's solution over the food. Heat the test tubes one at a time over the burner, using the tongs to hold the test tubes. What will happen: Benedict's solution is blue. The presence of sugar will turn the solution to orange. Are there some foods you thought were sugar-free that have sugar? This experiment will lead your children into discovering that many food items have sugar in them. "Benedict's solution" can be attained through the web link provided (see Teacher Resources.)
Classroom Activity # 8: "Fat Attack!"
Objective: Students will extract oils from nuts or seeds, as well as creating "butter" by coalescing fat from various types of cream and milk. Students will be introduced to fats and oils. They will learn which are better overall in one's diet. The links provided have simple experiments that can be replicated in any classroom. To extract fats from nuts, simply have them put any type nuts between sheets of paper towel, brown school paper towels work best. They will proceed to utilize a rolling pin to crush the nuts or seeds between the paper towels thus releasing the nut or seed oil. Experiments in making butter should use a variety of milk products (crème, skim, ½ and ½, whole milk, etc) to let the children see how much actual milk fats will coalesce into solid butter from each. Butter making activity websites are listed (see Teacher Activities.)
Classroom Activity # 9: "Vitamins"
Objective: Students will compare and contrast the vitamin "c" content of various juices based upon brand labels and prices. Students will define what a vitamin is. They will identify specific vitamins in their foods and beverages based upon base knowledge of food labeling, etc.
Background Information: Do different varieties of the same fruit have the same level of vitamin C? What about different brands of orange juice or fresh juice compared to juice from frozen concentrate? Does the way a fruit is stored (or) how long it is stored change the level of vitamin C? Background Info: Most birds and animals make their own vitamin C. Nevertheless, a few species, like people and guinea pigs, must get it from their food. Good sources of vitamin C are citrus fruits like oranges and grapefruit, strawberries, green peppers, broccoli and potatoes. Vitamin C is required for the body to make and maintain collagen, a protein. Collagen forms the base for all connective tissue in the body. If you do not have enough vitamin C in your diet, you might get the disease scurvy. Symptoms include loss of appetite, bleeding gums, loose teeth, swollen ankles, and tiny hemorrhages (bleeding spots) in the skin.
Procedures:
These are procedures to test for vitamin C content. (With this method, you can compare relative vitamin C content and rank juice beverages from highest to lowest, but you will not be able to get exact concentrations.) You will need some 2% iodine solution (find it at your local pharmacy) to prepare the vitamin C indicator solution described in the following: Step 1. Mix 1 tablespoon of cornstarch into enough water to make paste. Step 2. To this paste, add 250 milliliters of water and boil for 5 minutes. Step 3. Add 10 drops of the starch solution to 75 milliliters of water (use an eyedropper). Step 4. Add enough iodine to produce a dark purple-blue color. Now your indicator solution is ready. Step 5. Put 5 milliliters of indicator solution (about 1 teaspoon) in a 15-milliliter test tube (one for each sample). Step 6. To the test tube, use a clean eyedropper to add 10 drops of juice from the fruit or beverage (for solids, pulp them in a blender and strain the juice). Re-clean the eyedropper for each sample. Step 7. Hold the test tube against a white background. Line up the tubes from lightest to darkest purple. The lighter the final solution, the higher is its vitamin C content. That is because vitamin C causes the purple indicator solution to lose its color.
Classroom Activity # 10: "Minerals"
Objective: Students will learn what a mineral is. They will relate it to their previous studies using a variety of natural samples. Students will use magnets to "extract" the iron from a variety if breakfast cereals in order to determine which has the highest concentration of iron per daily serving size. "Total" will be the best of all brands. The iron in ready-to-eat breakfast cereals is in the form called elemental, not in combination with any other chemical compound. The outsides of cereal flakes were sprayed with a layer of iron particles. You can separate the iron with a strong magnet. Iron is essential in a healthy diet to build blood. Iron is easiest to absorb from meat, fish, and poultry.
Procedure:
You will need a sensitive scale for this procedure. A bathroom scale will not cut it!
- Crush 1/2 cup of cereal in a baggie, until the flakes are half their original size. Pour into a bowl.
- Add 1 cup of hot water and mix with a wooden spoon.
- Get a strong, 3-inch bar magnet that is not grey or black (so the iron filings will show up). Do not use a horseshoe magnet.
- Put the magnet into the cereal mix and stir gently in a circle for a fixed amount of time, say 5 minutes. Try not to bump the bottom or sides of the bowl.
- Take out the magnet. Remove the iron filings that it pulled from the cereal, and weigh them on a laboratory scale.
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