Chemistry & Nutrition: How’s Your Diet? (SOL 4.1)

Teacher Name: Gemma Griffin
Grade Level: 4-5

Subject: Science
Time Frame: 1 hour 45 minutes
Concept: Food Chemistry
Topic: Health and Nutrition


Providing students with hands-on experience and knowledge about good nutritional practices is essential to both their mental and physical, life-long well-being. It also provides them with a relevant and meaningful opportunity to think critically and practice scientific observation skills.

Goals: The student will gain a deeper awareness of healthy nutritional practices.

The student will practice science inquiry skills with a topic both meaningful and important to their lives and well-being.

SOL: Science:

4.1 – The student will plan and conduct investigations in which distinctions are made among observations, conclusions, and predictions.


Science as Inquiry:

– abilities necessary to do scientific inquiry
– understandings about scientific inquiry

Physical Science:

– properties and changes of properties in matter

Science in Personal and Social Perspectives:

– Personal Health



The student will be able to investigate and compare starch and fat found in various foods, both orally and in writing, evidenced by successful completion of experiment and accompanying data sheet.

The student will be able to design a healthy diet, based on knowledge gained from an experiment testing starch and fat in food, evidenced by a written meal plan.


The student will be able to personalize the importance of good nutritional habits, evidenced by their creation of a healthy meal plan.


The student will be able to conduct tests for starch and fat, major nutrients found in foods, evidenced by completion of experiment and accompanying data sheet.


Easy Science Activity Journals p. 26-27.
Zap! Blink! Taste! Think! Recording sheet p.67
Zap! Blink! Taste! Think! Concept sheet p. 178-179

Per group:

2 sheets of copy paper
Aluminum foil
cookie tray
Tincture of iodine (available at pharmacies in first-aid section)
1 eye dropper
Variety of food samples
1 pen/Fine tipped sharpie
1 sturdy drinking glass
gloves (1 per student)
goggles (1 per student)
Advanced Organizer: (15-20 min)

How’s Your Diet journal entry from Easy Science Activity Journals p. 26-27.

Discuss with students the importance of a healthy diet, and the food pyramid.

Procedures & Activities: ( 1 hour 25 minutes)

I. Getting Ready (10-15 min)

1. Have a variety of food collected before hand (bread, jam, cereal, orange juice, yogurt, peanut butter, chocolate, bananas, apples, chips, cookies) are a few good choices.

2. Introduce the food choices to your students.

3. Explain what a fat and starch is, including the benefits and negatives of each in our diet. (see concept sheet, Zap! Blink! Taste! Think! p.178-179).

4. Have them write down the names of the foods on the recording sheet (Zap! Blink! Taste! Think! p.67), and predict which ones will contain fat, starch, or both.

5. Have students share some of their predictions and reasons why.

II. Testing for Fat (20 min)

The big picture is that you will rub bits of foods on the labeled sections of absorbent paper. Once any water in the food has had time to dry, wet-looking, see-through spots on the paper tell you which foods contain fats or oils.

1. Draw as many circles as you have foods on one or two sheets of paper. Below each circle, write the name of one of the foods so that there is a place for each food you have chosen.

2. Put the paper on a tray of some sort so that they will be easy to move later without upsetting the foods you applied.

2. Drip, rub, spread, and or crush a small sample of the foods (room temperature or warmer) in the proper circles on the paper. A few drops of a liquid or a peanut-sized solid is enough. Dry foods such as nuts won’t give an accurate test unless they are crushed. Press down firmly with the bottom of a small glass to crush them into the paper. Wipe of glass for each time you must crush. Leave a piece of any solid food sitting in the circle. 3. Continue until you have applied all the foods.

4. Allow the papers to dry for about 35-45 minutes in a warm, preferably sunny spot. If much fat is present, the paper will turn and stay translucent (partly see-through) around the food sample.

While we’re waiting for our fat results:

III. Testing for starch (20 minutes)

The starch test is an instant chemical test. Add iodine to a food sample and see if a color change to purple or blue/black occurs. Warning: Iodine is poisonous. Students should be instructed not to eat any of the tested samples and to wipe up spills and put all the samples in the trash when finished.

1. Work on foil for this set of tests. Draw and label circles on the foil with a fine tipped marker, one circle for each food.

2. Place a sample of the food in each circle. It need not be crushed or smeared.

3. Use the eye dropper to take up some of the iodine and add one drop of it to each food sample. Do not touch the food with the eye dropper so you don’t mix one food with the next.

4. A blue/black or purple color shows that starch is present. The iodine alone is a rusty orange color. Dark colored foods such as grape jelly or chocolate will be harder to analyze.

5. Record you results on the record sheet by writing a plus (+) for food where starch was present and a minus (-) where it was not found. If you are not sure, record a question mark.

Because Iodine is a poisonous substance, teacher’s, depending on the maturity of their students may wish not to do the iodine test. Another way you could test for starch was to test the absorption abilities of different foods in water. Example: Bread is more starchy than an apple slice, and also absorbs more water.

IV. After break, come back to record the fat results. Record your results on the recording sheet. A plus sign means that fat was detected and is called a positive test. A negative sign means no fat was detected. If you are not sure, record a question mark. (10 minutes)

V. Compare predictions with your test results for both fat and starch. (10 minutes)

Discuss with the class which foods contained most fat, least fat? (least starch, most starch?)

Closure: (10-15 min)

With a partner, take a look back at your journal were you recorded what you ate yesterday. Now based on what you know about fat and starchy foods, the food pyramid, and characteristics of some types of foods, plan and illustrate a menu for a meal tomorrow!


Experiment completion.

Data sheet: predictions made, fat and starch test results recorded.

Menu plan (Culminating assessment).