Minds On

What does estimation mean to you?

What comes to your mind when you think of the word “estimation”? Have you estimated before?

  • Estimation is when we use the information and we have to make a thoughtful guess.
    For example, we can estimate how many steps it will take to get from one place to another place. How to measure using steps:
    • Put your foot down
    • Put your other foot in front
    • Make sure your front foot is touching the back foot
    • Count each step you take
    How many steps are you away from your entry door? Record your estimate on paper or in an audio recording.
  • Estimation is a useful mental strategy when either an exact answer is not needed or there is insufficient time to work out a solution.

Activity

Guess how many steps or ruler lengths you are away from your entry door. Write your estimate on a piece of paper.

Here is a picture of a girl measuring using their steps.

What does estimation mean to you?

A girl using her feet to measure distance.

Student Success

Think-Pair-Share

Either walk from where you are to the entry door or check the distance with a ruler.

Is your estimate was close to the answer?

Note to teachers: See your teacher guide for collaboration tools, ideas and suggestions.

Record your thinking

Record your ideas using a voice recorder, speech-to-text, or writing tool.

  • What was your estimate? Is it close to your measuring result?
  • What are some factors that will affect your result? (i.e., shoe sizes)

Action

Activity 1

10 can help!

When we estimate (or guess) how many of something there are, knowing how much space 10 of them takes up, it makes the job easier.

If this is the space 10 stars takes up, estimate how many stars are in each of the other boxes.

A box with 10 stars.

Estimate #1:

A box with 23 stars.

Estimate: (Blank)

Press the ‘Actual’ button to reveal how many stars are in the box.

23

Estimate #2:

A box with 41 stars.

Estimate: (Blank)

Press the ‘Actual’ button to reveal how many stars are in the box.

41

Activity 2

In this activity, there is a jar with beads. Before exploring the clues, estimate how many beads are in the jar.

As the clues appear, use the information to narrow the possibilities to come as close to guessing the answer as possible. Then, use your estimation skills to determine the final answer.

A clear jar with dozens of beads inside.

Press the ‘Hint’ buttons to reveal hints about the jar.

The answer is a 2-digit odd number.

The answer is between 60 and 90.

You say this number if you skip count by 5s from 0 for a long time.

65,75,85 are all the possible answers

Activity 3

Estimate how many crackers are in this bowl. Before you begin, consider:

  • What size do fish crackers come in?
A clear bowl that has 110 fish crackers inside.

Brainstorm

Brainstorm

How do we know our estimate is correct? Is it close? What can we do to check?

Let’s check your answers with hints.

Press the ‘Hint’ buttons to reveal clues about the bowl.

The answer is a 3-digit even number.

The answer is between 100 and 130.

You say this number if you skip count by 10s from 0.

Here's the answer!

110, 120 are both possible.

Consolidation

Activity

Today, you will create your own mysterious number.

Find a clear container (e.g. plastic bag, glassware, jar).

Fill the container with the same type of objects (e.g. Lego pieces, one type of fruit, fish crackers, markers/crayons).

Skip count the items in your container and write down your result. You can choose to skip count by 2s, 5s, 10s, 20s, 25s or 50s.

Now, fill the container again without counting the objects as you put them in. Estimate the number of objects in the container and record your answer in your notebook.

Now count the objects that are in the container. How close was your estimate?

Reflection

How do you feel about what you have learned in this activity?  Which of the next four sentences best matches how you are feeling about your learning? Press the button that is beside this sentence.

I feel...

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