## What Is the Best Chip?

- Lesson

In this investigation, students use data analysis to seek answers to
the types of questions often posed by consumer agencies and people who
work in sales and marketing. This lesson was adapted from the article
"Consumer Investigations: What is the "Best" Chip?" by Dixie Methany,
which originally appeared in the March 2001 issue of *Teaching Children Mathematics*.

### Day 1: Preparing for the Investigation

Display the bags of chips to be used for the investigation, for instance, potato chips, tortilla chips, or banana chips. This investigation does not involve the brands of chips, but teachers might design an extension to compare brands of one type of chip.

Hand out an index card to each student, and ask students to write down which chip they think is the best and why.

Divide the students into groups of three, and ask them to read their responses to their groups. Ask a representative from each group to report on the group's discussion. On chart paper or the board, record the criteria that the students used to determine the best chip. This discussion should help students recognize the difference between qualitative and quantitative responses, and they should sort the responses into those two categories. For example, some students might use qualitative criteria, such as flavor for banana chips, crispiness for potato chips, and similar attributes. Others might use quantitative data, such as cost, calories, total fat, and so on.

Discuss with the class the criteria that they used to determine the best chip, distinguishing between qualitative and quantitative criteria. Have students select the quantitative criteria, such as calories, total fat, sodium content, protein, cost per ounce, number of chips per ounce, and so on, that they can use to determine the best chip. Discuss how to compare different chips when the servings are not the same size.

Help the students design a rubric that they can use during the investigation for each quantitative criterion. The class discussion should generate a description of each level of the rubric by determining when a high or low value would be better for each of the criteria and why. The class chart might resemble the following:

Calories | Less than ____ calories | Between ____ and ____ calories | More than ____ calories |

### Day 2: Structuring the Investigation

Tell the students that they are preparing reports on the best snack chips for a consumer magazine. Their reports should include accurate information, use visual aids to show the information, be well organized, and have a conclusion or recommendation.

Use the data about calories to model product testing. Discuss ways to present the data, such as through tables,
charts, or graphs.

Distribute calculators and bags of chips or copies of the nutrition facts, weight, and cost facts to each group. Distribute the Chips for Sale Activity Sheet to each student.

Each student should record the requested information for his or her brand of chip. Have the groups develop criteria for high, medium, and low values for the other quantitative data. A sample template is shown below.

Allow time for the students to work in groups to gather the information on each type of chip from the labels. Students can organize this information using charts, tables, or bar graphs, as they did for the calorie content.

**Sample Criteria**

Calories | Less than ____ calories per serving | Between ____ and ____ calories per serving | More than ____ calories per serving |

Total Fat | Less than ____ percent per serving | Between ____ and ____ percent per serving | More than ____ percent per serving |

Sodium | Less than ____ milligrams per serving | Between ____ and ____ milligrams per serving | More than ____ milligrams per serving |

Protein | Less than ____ grams per serving | Between ____ and ____ grams per serving | More than ____ grams per serving |

Cost per Ounce | Less than ____ per ounce | Between ____ and ____ per ounce | More than ____ per ounce |

Using the information gathered, decide which chip is the best by discussing the criteria. For example:

- Which chip has the fewest calories?
- Would cost be a consideration if a certain type of chip contains less fat or sodium?

The teacher should circulate among the groups to facilitate their work, ask groups to explain their thinking, and clarify any misconceptions about the investigation that the students might have.

### Day 3: Concluding the Investigation

Before groups share their data with their classmates, it is important that they have a discussion about the relative "healthiness" of the chips they studied. Even the chip they determined to be the best chip may not be a healthy snack selection. Students should compare the nutrition information of healthier snacks, such as apples, carrots, and the like with their chip data. Students can research nutrition information online. The Food Pyramid is a good starting place for general nutrition information.

Students should use the web to obtain specific nutrition data for their healthy snacks.

The groups give presentations to the class, using the charts, tables, or graphs that they developed to determine the best chip. The students should evaluate the presentations given by their classmates. They should make sure that the calculations are correct, that the visual aids are readable, and that the presentations support the criteria for the best chip. The class may also discuss the idea that best means different things to different people according to what they value most.

- 3 × 5 index card
- Paper and pencils
- Three small bags of different brands of chips (for each group)
- Calculators
- Chips for Sale Activity Sheet

**Extensions**

- Students can discuss ways to compare qualitative criteria, such as taste, and develop and test a rubric related to taste.
- Students can conduct a survey to determine which chip the teachers and other students in the school think is best. The class can then compare the results of the survey with the results of the classroom investigation.
- Students can conduct a similar investigation to compare specific brands of one type of potato chip or tortilla chip, using qualitative or quantitative criteria.
- Students can graph calorie content, total fat, and so on, for each type of chip, using a spreadsheet as part of their presentations.
- Students can do research from consumer guides or on the Internet to evaluate other foods that they like.
- Students can use the information that they have gathered to write an advertisement for the best product. Students should base the advertisement on the criteria used to select the best product.

### Learning Objectives

Students will:

- Gather data.
- Organize data into tables or charts.
- Distinguish between qualitative data (qualities such as taste and crispiness) and quantitative criteria (measurable amounts).
- Use the data and criteria to choose the "best" chip.
- Identify and use multiple approaches for solving problems.
- See connections between mathematics and such other disciplines as consumer research, sales, and marketing.

### NCTM Standards and Expectations

- Design investigations to address a question and consider how data-collection methods affect the nature of the data set.

- Collect data using observations, surveys, and experiments.

- Represent data using tables and graphs such as line plots, bar graphs, and line graphs.

- Propose and justify conclusions and predictions that are based on data and design studies to further investigate the conclusions or predictions.