Ask the students to name their favorite kind of fruit. As they do so, write each one on the board. Then ask each student to place a tally mark next to his or her favorite fruit. When all have done so, ask what kind of fruit was named most often. Now display a large bar graph and call on volunteers to title the graph, label the rows with the fruits named, and fill in the number of squares in that row that is equal to the mentions that kind of fruit received. Now ask the students to compare the rows of the graph by posing a question such as, "How many more students liked apples than liked oranges?" Next, encourage the students to generate similar questions, and call on their peers to answer them.
Now assign the students to groups of four students each. Hold up a fan of index cards so that the students cannot see what is written on them and ask each group to take one card.
Note:Before the lesson, write on separate file cards survey questions and three or four answers. Such questions could include:
- Which color do you like best: red, yellow, blue, or green?
- What is your favorite pizza topping: pepperoni, mushroom, or plain cheese?
- What ice cream flavor do you like best: vanilla, chocolate, or strawberry?
- What is your favorite subject: math, reading, social studies, or science?
Next ask the group to make a tally chart on
which they can record the answers to their question.
Tally Chart
FAVORITE COLORS
| Blue |
| | | |
| Red |
| | | | |
| Yellow |
| | | |
| Green |
| | |
Encourage the students to think of a way that they can survey at least ten classmates. Allow plenty of time for the students to collect the data, and then ask them to make a bar graph.
Distribute Graph Paper to the students.
Students should create a bar graph on the graph paper.
When they have done so, ask them to think of four questions they can answer by looking at their bar graph.
Bar Graph
FAVORITE COLORS
You may wish to circulate around the room to be sure that all students can enter their data on their bar graph. When they are ready, ask each group of students to tell the class what they know about their fellow students from
looking at the bar graph that they have created. [Although the students may start with questions that can be answered by simply looking at the length of one bar, encourage them to ask questions that require the comparison of two or more
bars as well.] Lead the students to notice which bar was the longest and which the shortest. [You may choose to tell 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 display the NCTM Bar Grapher tool.
Now ask one group to enter their data into the recording section. Ask them to choose a name for the bar graph and the colors of bars that they would like for each bar. Then ask questions about the bar graph such as: How many more students liked red the best? Did more students like blue than liked green? Encourage the presenting group to pose other such questions and call on classmates to answer them. [The graphs are printable, so you may want to print a copy for a class display.] Then allow the other groups to enter their data and ask their questions.
End the lesson by encouraging the students to copy the bar graph and to write three things they learned from it for their portfolio.
