Students will use common household measurement tools and scientific measurement tools and various methods of measurement to compare for accuracy. Students will also calculate percent error by comparing their measurements to actual values and apply these principles to analyze and decipher the components of a food as indicated on the Nutrition Facts label. Grades 6-8

accuracy: occurs when measurements are close to a quantity’s actual value

cups: a unit of volume that is most commonly used to measure most liquids, but can also measure dry ingredients

density: the mass of a substance per unit of volume

gram: a unit of weight equal to the mass of 1 cubic centimeter (cm3) of water at 4°C

mass: a measure of the amount of matter, or a measure of the force of gravity between two objects

matter: a material substance that makes up all physical objects and occupies space

meniscus: the curved upper surface of a column of liquid

precision: the quality, condition, or fact of being exact and accurate

volume: the amount of space an object occupies

1. Display a Nutrition Fact label for your class to see.
2. Ask the following questions, "How are weights and measurements used in this Nutrition Fact label?" Use further guided questions if necessary for students to recognize and point out that each nutrient is measured in grams or milligrams.
3. Ask students how these measurements are taken and how they can help us.
4. Give each student one copy of the Everyday Weighing and Measuring student handout. Instruct students to complete the worksheet (in class or as homework) using a Nutrition Fact label of their choice. Students can find food labels in the grocery store, USDA’s FoodData Central, or use the labels provided in this lesson.
   • Note: If the student chooses to use the provided food label, see the attached Everyday Weighing and Measuring Teacher Key for answers to the lab questions. Answers to questions based on other food labels will vary.
5. If this activity is completed in-class, allow students to work in small groups on the lab sheet to further explore the topic and respond to questions.
6. Follow-up with a class discussion about student findings related to their favorite snacks and student generated ideas for choosing healthy snacks.

Food Exploration Lab 1: Mastering Measurements

Teacher Preparation:

1. Review information found in the Background Agricultural Connections section of the lesson, lesson Procedures, and the attached Essential Files.
2. Prepare lab materials for each group:
   • Assign 3 groups to Assignment A and 3 groups to Assignment B.
   • Fill 1 plastic bag per group (assigned to Assignment A) with 1 and 1/2 cups of flour
   • Fill 2 plastic cups per group (assigned to Assignment B) with liquid ingredients (1 cup with water, 1 cup with cooking oil)
     • Note: If you have 6 student groups, 3 groups will use flour (Assignment A) and 3 groups will use liquids (Assignment B).  
3. In the lab investigations, students will be measuring and massing ingredients, calculating percent error, and converting measurements. Consider reviewing with students how to tare a scale, how to properly measure dry and liquid ingredients, how to calculate percent error, and how to convert between common measurements (e.g. ounces to cups, cups to tablespoons).

Lab Procedures:

1. Give each student one copy of the Mass Measurements student handout.
2. Ask students to read pages 1-3 and complete the "Think About It" focus questions on page 4.
3. Prepare students to begin the lab investigation by requiring students to wash their hands and emphasize the importance of practicing good food safety behaviors by not consuming substances used as part of the lab investigation.
4. Distribute lab materials. It is recommended that materials are organized into stations for easier distribution. Students should be arranged in small groups of 4-5. Each group should receive the lab supplies outlined in the Materials section as well as 1 copy of the Mastering Measurements lab sheet.
5. Launch the lab by asking students to make a prediction about accuracy of methods and precision of tools used when measuring ingredients. Show students the Weights & Measures Lab I Demonstration Video. Then give them time to complete their lab exploration following the instructions found on the Mastering Measurements lab sheet. Students should discover the following: 
   • Dry Ingredient (Flour): The most accurate method for measuring flour is the sifted method. In cooking, it is recommended that flour be sifted before measuring. Flour tends to be a more difficult ingredient to measure due to its tendency to pack down, which increases the density of the ingredient.
   • Liquid Ingredients (Cooking Oil & Water): The oil and liquid should weigh approximately the same regardless of the tool used to measure them; however, students will observe a difference in the accuracy of measurement. The liquid measuring cup should allow students to observe and measure the amount of liquid using the meniscus; however, that does not necessarily mean the measurement will be completely accurate. The dry measuring cup does not allow such accuracy when measuring liquids and is more prone to spilling (human error). Both of these common kitchen tools should prove to be the least accurate. Of the three tools, the graduated cylinder will be the most accurate. The graduated cylinder should have the most graduations allowing the observer to measure to the nearest milliliter. When comparing the two liquids, the relative density of cooking oil and water differ, resulting in different weights of each. Oil has a lower density compared to water, and therefore weighs less per unit volume.
6. Once the lab is complete, allow students to work in small groups to complete their lab sheet to further explore the topic and respond to lab questions.
7. Follow-up with a class discussion about the importance of accurate methods and tools in science. See Enriching Activities for ideas on how to further extend this lesson.
   • Optional: Explore accuracy further using different methods and measurement tools (e.g. beaker)

Food Exploration Lab 2: Label Logic

Teacher Preparation

1. Review information found in the Background Agricultural Connections section of the lesson and the attached Essential Files.
2. Prepare materials for each group by pre-labeling cups for each student group. Label each cup with an ingredient name (i.e. salt, sugar, butter, and olive oil). Each ingredient should have two labeled cups (one filled, one empty). Fill each cup approximately 1/4 full with salt, sugar, butter, and olive oil. 

Lab Procedures:

1. Distribute lab materials. It is recommended that materials are organized into stations for easier distribution. Students should be arranged in small groups of 4-5. Each group should receive the lab supplies outlined in the Materials section as well as 1 copy of the Label Logic lab sheet.
2. Prepare for lab by requiring students to wash their hands. Emphasize the importance of practicing good food safety behaviors by not consuming substances used as part of the lab investigation. Show students the Weights and Measures- Label Logic video to demonstrate the lab.
   • Note: Be sure students read Mass Measurements and completed the focus questions as outlined in Lab 1. 
3. Launch the lab by asking students to begin following the instructions on their lab sheet. Students should conclude the following:  
   1. Snack #1 – Classic Potato Chips: Students should find the classic potato chips have more calories, fat, and sodium. 
   2. Snack #2 – Baked Potato Chips: Students should find the baked potato chips have fewer calories, grams of total fat, and sodium. The baked chips also contain more fiber. However, the baked chips do contain more sugar. Overall, due to the lower number of calories and fat grams and higher fiber content, baked chips are the better option.
4. Allow students to work in small groups to complete the lab sheet and respond to lab questions.
5. Follow-up with a class discussion about reading Nutrition Facts labels to obtain health information about food. See Enriching Activities for ideas on how to further extend this lesson.
   • Optional: Have students bring in labels of their favorite snacks to review as a class.

After conducting these activities, review and summarize the following key points:

• Food labels are used to indicate the nutrition value of foods.
• Accurate measurements and conversions are used to create accurate food labels.

This lesson was partnered with East Carolina University. The FoodMASTER program was supported by the Science Education Partnership Award (SEPA) which is funded from the National Center for Research Resources, a component of the National Institutes of Health.

• Primary Authors:
  • Virginia Stage, PhD, RDN, LDN
  • Mary White
  • Ashley Roseno, MAEd, MS, RDN, LDN
  • Melani W. Duffrin, PhD, RDN, LDN
• Graphic Design: Cara Cairns Design, LLC

• Eat Happy Project video series
• How to Read Nutrition Facts - Food Labels Made Easy video
• Labels Unwrapped
• Nutrition Research Articles