## The Eyes Have It

Look at Me
Pre-K-2
1

Students collect data about the eye color of class members. They create bar graphs with several classifications of data. They pose and answer questions about the data by looking at the graph, and they find the range and mode.

Explain to students that you would like to know what eye colors are represented in the class. Give each child an index card and crayons. Ask the students to find a partner and write the color of their partner's eyes on the index card. Encourage them to write as large as possible, using a crayon color that matches the color of the student's eyes. Then ask the students to give their partner the card that shows his or her eye color.

Now gather the students around you and ask them to display their index cards. Invite them to make a tally mark (only one Tally Chart will be used to record data from each of the students in the class) on the chart paper. A sample tally chart is shown:

The Color of Our Eyes
 Blue Brown Black Green

Tell the students to line up if the color of their eyes is blue. Then call out other eye colors and have the students line up in parallel columns until all the class members have lined up and formed a human bar graph.

Next, ask the first one in each row to collect the cards from that group and tape them on the board to form a bar graph. Solicit a name for the graph from the students. Ask the students to take their seats and give each Graph Paper.

Instruct them to fill in the bars with the color of crayon that matches the eye color displayed in that bar of the graph. You may wish to move around the room to be sure that all students can complete a bar graph from the data.

Ask the students what they can tell about the eye colors in the class from looking at the bar graph. After the students give several statements, encourage them to use numbers to describe the graph. You might begin by asking questions about the number of students with a certain eye color. The next set of questions might compare two bars on the graph. Lead the students to notice, which color was most frequently represented and which were least represented. Inform them that the difference between these numbers is called the range. Ask them to subtract to find the difference between the greatest number and the least number in their set of data.

Next, inform them that the number found most often in a set of data is called the mode. Ask them to identify the mode in this set of data.

Using the Bar Grapher Tool, create a bar graph of the class data.

Call on students to choose a name for the bar graph and the colors of the bars.

Ask students how the computer-generated graph is similar to the bar graphs they created on graph paper.

Assessment Options

1. You may wish to record the progress of individual students toward the learning objectives in this lesson on the Class Notes recording sheet. Making a note of this information now may be useful when later discussing students' levels of achievement with them and their parents.
2. Collect the bar graphs students created by hand for their portfolios. Save a copy of the bar graph for use later in the unit.

Extensions

1. You may wish to link this lesson to a life science unit. Students can discuss the functions of the eye, specifically the iris and eye color.
2. Move on to the next lesson, Up on Top.

Questions for Students

1. How many of us had brown eyes? Blue eyes? Other colors of eyes?

[Answers will depend upon student data.]

2. Which color did the fewest students have? What is the difference between the number of students with black eyes and those with green eyes?

[Answers will depend upon student data.]

3. What do we call the difference between the largest number and the smallest? What is the range of the data that we collected on eye color?

[The range; Answers will depend upon student data.]

4. Suppose you add my eye color to the graph. How would adding my color change the graph? Would it change the range?

[Answers will depend upon student data.]

5. What color did more students have than any other? How can you tell by looking at the bar graph? What do we call the eye color that appears the most often?

[(Respectively) Answers will depend upon student data. It has the longest bar on the bar graph. The mode.]

Teacher Reflection

• Were the students able to pose questions about the graph? Were they able to answer questions about the data using the graph?
• Were all the students able to identify which bar was the longest? Could they name it as the mode?
• Were they able to find the range of the data? Could they use the term "range" in appropriate ways?
• 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 graphical representations were easiest for students to create and interpret?
• Were most students able to create bar graphs?
• Would I make any adjustments the next time that I teach this lesson?

### Freckle Face

Pre-K-2
This lesson initiates the development of skills in collecting and recording data. Students collect data about a partner's face and tally the data from the whole class. They learn the convention for displaying a set of five using tally marks. Then students create a pictograph and pose and answer questions about the data set.

### Up on Top

Pre-K-2
In this lesson students generate bar graphs. Posing and answering questions using the graphs gives them an opportunity to apply their reasoning and communication skills. They also consider whether a given category is likely, certain, or impossible.

### Making Glyphs

Pre-K-2
In this lesson, students learn a powerful way to display data—using a glyph. They collect data and create pictures using the data. Students also interpret glyphs made by other students.

### Learning Objectives

Students will:

• Collect and classify data.
• Create a bar graph with several categories of data.
• Find the range and mode of a data set.

### NCTM Standards and Expectations

• Pose questions and gather data about themselves and their surroundings.
• Sort and classify objects according to their attributes and organize data about the objects.
• Represent data using concrete objects, pictures, and graphs.
• Describe parts of the data and the set of data as a whole to determine what the data show.