Minds On

Line plots

A community planner has sent you a graph that has important information about activities for a local fair.

Explore the graph that contains the information.

There is a picture of water balloon relay, bubbles, popsicle, obstacle course, bouncy castle and sidewalk chalk.

Describe the graph. What type of graph is it? What is its title? Tell as much as you can about the data. Record your thoughts using a method of your choice.

Action

Line plots

There are different ways to display sets of data. The graph in the Minds On, for example, is a line plot.

What is a line plot?

A line plot is a graph that shows a mark (usually an “X”) above a value on a number line. Each “X” is a piece of data or entry in a data set.

Let’s explore another line plot.

Growing bean plants

A Grade 2 class recorded the height of 20 bean seeds as they grew for two weeks.

Each day students measured how many centimetres their bean plant grew. They used a tally chart to record this data.

Picture of a bean plant.

Bean Plant Heights after Two Weeks

Height of Bean Plant after Two Weeks (cm) Tally Total
2 cm

1
4 cm

2
6 cm

3
8 cm

7
10 cm

5
12 cm

2

After two weeks, the students used the data they collected to create a line plot.

Explore the line plot below.

The title of the line plot is “Bean Plant Heights after Two Weeks.” The number line is labelled from 2cm to 12cm, going up by two’s.

The graph displays the data from the tally table using a number line.

To create a line plot, the students first created a number line that includes all the values in the data set. For example, the bean seeds grew from 2cm to 12cm, so the number line goes up by two’s from 2cm to 12cm.

Next, they placed an X above each data value on the number line.

Example: 1 tally mark for 2 cm means 1X over 2 cm on the number line.

Example: 7 tally marks for 8 cm means 7 X’s over 8 cm on the number line.

The measurements on the line plot display the height of each plant at the end of the two weeks.

What else do you notice? Answer the following questions independently or, if possible, with a partner:

Creating a line plot

Create a line plot using the data in the tally table below. You can use your notebook, or any other method of your choice.

Days of the Week Number of Birds Totals
Monday 1
Tuesday 3
Wednesday 6
Thursday 3
Friday 7

The data was collected by a Grade 2 class at a school in Oshawa, Ontario. The children counted how many birds visited the bird feeder outside of their classroom window every school day for a week.

Here are your steps:

  • Step 1: To create a line plot, create a number line that includes all the values in the data set: Monday, Tuesday, Wednesday, Thursday, Friday.
  • Step 2: Next, place an X above each data value. For example, 1 tally mark for Monday means 1 X over Monday.
  • Step 3: Once you have created your graph, examine it.

What do you notice?

What does the line plot tell us about the data?

How do you know? Record your thinking using a method of your choice.

Consolidation

Reflection

Use the following questions to reflect on your learning. You can type, write, use speech to text, or audio record your responses.

  • Describe how you create a line plot using data from a tally table.
  • How would you describe a line plot to a partner?

I feel…

Now, record your ideas about your feelings using a voice recorder, speech-to-text, or writing tool.