Purpose

In this unit students make statements about data displays. Students evaluate statements as true or false using the features of the data to support their evaluation.

Achievement Objectives

S2-1: Conduct investigations using the statistical enquiry cycle: posing and answering questions; gathering, sorting, and displaying category and whole-number data; communicating findings based on the data.

S2-2: Compare statements with the features of simple data displays from statistical investigations or probability activities undertaken by others.

Specific Learning Outcomes

- Make a statement about a data display.
- Decide if they agree or disagree with a statement about the data display.
- Give reasons to support their evaluation of the statement.

Description of Mathematics

In this unit students make statements to describe information shown in the data display. At this level students will be commenting on a variety of different data displays. Category data includes pictographs, bar graphs, strip graphs, and pie graphs. Whole number data includes dot plots and stem and leaf graphs. Students will make statements about data displays and support their statements using features of the data. Students are asked to evaluate statements made by other students. They will agree or disagree with the evaluation and give reasons for their opinions.

There is scope within this unit for teachers to include Statistical Investigations AOs if students collect data and prepare their own data displays.

Required Resource Materials

Activity

- Show the students the bar graph on Copymaster 1 or construct your own class bar graph on favourite fruit.
- Make a statement about the graph, for example “bananas are more popular than pears”.
- Ask the students to explain why this is true. Look for reasons that include the number of people who like bananas, the number who like pears and a comparison between the numbers.
- Ask a volunteer to ask a statement about the graph. Prompt the students to make statements, by asking : what fruit is the most popular? what fruit is the least popular? how many people like “x” fruit? what is more popular oranges or apples?
- After a student has made a statement. Ask another student to explain why it is true.
- Record statements and reasons alongside the bar graph.

In the next few sessions students will work in groups and pairs to make and evaluate statements about data displays.

Make and evaluate classmates’ statements

- Use graphs from Copymaster 2 or collect some category data from the students and display it as a bar graph or pie graph. Possible ideas include: pets, eye colour, favourite sports, favourite books etc.
- Have students work in pairs. The first student makes a statement about the graph then the second student decides if they agree or disagree with the statement and provides a reason. The students then reverse roles. For example: “The most popular pet is a cat” “I agree because 12 people have cats and the next tallest bar in the graph is 10 people with dogs

Agree or disagree with statements

- Use the graphs from Copymaster 3 or collect data from the students and make your own graphs.
- Give the students copies of graphs from Copymaster 3. Ask students to decide if they agree or disagree with the statements made.
- Ask students to make two statements about each of the graphs.

- Use the graph in Copymaster 4 or collect data from the students and make your own graph.
- Ask a student to make a statement about the graph, it can be true or false. Other students vote if they agree or disagree with the statement.
- Ask the students to give reasons for whether the statement was true or false.
- Organise the students into groups and repeat this activity in groups.

Attachments

true-or-false-4.pdf138.11 KB

true-or-false-3.pdf149.97 KB

true-or-false-2.pdf215.23 KB

true-or-false-1.pdf124.46 KB