Illuminations: Eat Your Veggies

Eat Your Veggies

Healthy Eating

Students collect data about classmates' healthy food knowledge. They create bar graphs, pose and answer questions about the data by looking at the graphs, and find the range and mode.

Learning Objectives
 
Students will:
  • collect and classify data
  • create a bar graph with several categories of data
  • pose and answer questions about a set of data
  • find the range and mode of a data set

Materials
 
Computer with Internet access
Bar Graph Format
Class Notes Recording Sheet
Graph Paper (optional)

Instructional Plan

You may wish to begin the lesson by reviewing the color classification system on the 5 A Day the Color Way Web site. [You may wish to print out "The Colors of Health" from the 5 A Day web site, so that students can refer to the foods in each category.] Then ask the students to notice the five colors into which the fruits and vegetables are classified [blue/purple, green, white, red, yellow/orange.]

Organize students in five groups, and assign each group a color. Tell them to list as many fruits and vegetables as they can that correspond to their assigned color. You might encourage them to look at the food pyramid for ideas. After you have given students time to work, gather the students around you and ask them to display their lists. Invite them to make a tally in the row of a tally chart you have drawn on the board for each food they identified.

 

Number of Fruits and Vegetables Listed

Blue/Purple  
White  
Red  
Green  
Yellow/Orange  

 

Solicit a name for the tally chart from the students. Ask the students to take their seats and give each student a copy of the Bar Graph Format.

Bar Graph Activity Sheet Bar Graph Activity Sheet

Ask the students to use the data from the class to make a bar graph. [You may wish to circulate to be sure that all students can complete a bar graph from the data.] Now ask the students what they can tell about the data from looking at the bar graph. Depending on the students' familiarity with creating bar graphs, they may use graph paper instead.

After the students have offered several statements, encourage them to use numbers to describe the graph. You might begin by asking questions about the number of foods that the students had listed for each given color. The next set of questions might compare two bars on the graph. Lead the students to notice which color had the longest bar and which color had the shortest bar. Inform them that the difference between these numbers is called the range, and ask them to compute the range by subtracting the lowest number from the highest number. Identify this as a measure of spread. Next, inform them that the number that occurs most often in a set of data is called the mode. Ask them whether this set of data has a mode. [If two numbers occur more than the others, the data set is called bimodal.] Tell them that the mode is one of three measures of central tendency.

Next, students should go to Create A Graph from the National Center for Education Statistics, and select the "Bar Graph" option. Ask volunteers to enter the class data into the recording section. Call on students to choose a name for the bar graph and the colors of bars that they would like in the bar graph. Then select a student to hit the “Generate graph” command. [Note that you can generate either a vertical or a horizontal bar graph with this software. You may wish to show the students each of the orientations and ask them to compare them. Lead them to notice that changing the orientation does not affect the data.] After the students have discussed the graph, select the "Printable Graph" option and print out the bar graph for future reference.

Questions for Students
 
How many green foods had been tasted? Blue and purple foods? Other colors of food?
[Answers will depend upon student responses.]

For which color were the fewest foods named? The most? How do you know? For which color were the students able to name the most foods? The next most? How can you tell by looking at the bar graph?

[Answers will depend upon student responses.]

What do we call the difference between the largest number and the smallest?

[The range.]

What is the range of the data that we collected when we named foods by color?

[Answers will depend upon student responses.]

Suppose I named four more green foods. How would the graph change? Would the range change? The mode?

[Answers will depend upon student responses.]

Assessment Options
 
  1. At this stage of the unit, it is important to know whether the students can do the following:
    • Collect and classify data
    • Create a bar graph
    • Pose and answer questions about a set of data
    • Find the range and the mode of a data set
  2. You may find it helpful to use the Class Notes recording sheet to record the progress of individual students toward the learning objectives in this lesson. These notes may be useful when later discussing students' level of achievement with them and their parents. Such records will also provide documentation for future lesson planning.

Extensions
 
  1. To extend and record the learning that occurred in this lesson, ask the students to write their first names on the board. Then ask them to work in groups to make a bar graph showing the length (with regard to the number of letters) of the first names in the class. Ask them to find the mode and the range of that data set. You may wish to collect these worksheets for the students' portfolios.
  2. Students may also wish to use one of the NCTM applets for creating bar graphs. They can use the Bar Grapher in place of the previously mentioned bar graphing tool, or they may use both tools and compare the graphs created.

    Bar Grapher Bar Grapher

Teacher Reflection
 
  • What help, if any, did you need to give students when creating the bar graphs?
  • Were all students able to pose questions about the graph? Were they able to answer questions about the data using the graph?
  • Were all students able to identify which bar was the longest? The shortest?
  • Were the students able to find the range of the data? Could they use the terms "range" and "mode" appropriately? What evidence do you have of this?
  • Which students met all the objectives of this lesson? What extension activities would be appropriate for those students?
  • Which students did not meet the objectives of this lesson? What instructional experiences do they need next?
  • Which groups worked well together? Which needed more careful monitoring?
  • Would I make any adjustments the next time that I teach this lesson?

NCTM Standards and Expectations
 
Data Analysis & Probability 3-5
  1. Represent data using tables and graphs such as line plots, bar graphs, and line graphs.
  2. Collect data using observations, surveys, and experiments.
  3. Design investigations to address a question and consider how data-collection methods affect the nature of the data set.
  4. Describe the shape and important features of a set of data and compare related data sets, with an emphasis on how the data are distributed.
This lesson prepared by Grace M. Burton.
  
1 period   

NCTM Resources

Principles and Standards for School Mathematics

Web Sites
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