# Lesson 10 Estimation Exploration

Let’s design an Estimation Exploration activity.

## Warm-up Estimation Exploration: No Driver Required

Here are pictures showing the exterior and interior of a parking tower in Wolfstadt, Germany. The parking is automated: each car goes up on a lift and is then placed in a parking space.

How many cars can fit in the tower?

Record an estimate that is:

too low | about right | too high |
---|---|---|

## Activity 1 Dental Care

## Problem 1

Jada brushes for 2 minutes, twice a day. She changes her toothbrush every 3 months.

Based on this information, make some estimates and show your reasoning:

In a lifetime, approximately:

How many toothbrushes will she use?

How many dollars will she spend on toothbrushes?

## Problem 2

About how many minutes would she spend brushing her teeth:

in a year?

in a lifetime?

## Problem 3

Think of another estimation question you could ask about this situation.

## Activity 2 Get Your Classmates to Estimate

It’s your turn to create an estimation problem.

Think of situations or look around for images that would make interesting estimation problems. Write down 4–5 ideas or possible topics.

Choose your favorite idea. Then:

Write an estimation question that would encourage others to use multiplication of multi-digit numbers to answer.

Record an estimate that is:

too low

about right

too high

## Activity 3 Facilitate Your “Estimation Exploration” Activity

Follow these steps to facilitate your Estimation Exploration activity for another group:

Display your image or present your scenario.

Ask your classmates: “What is an estimate that’s too high? Too low? About right?”

Give them 1 minute of quiet think time.

Give them 1–2 minutes to discuss together.

Invite them to share their estimates and how they made them. Record their ideas.

If you know the actual number or quantity, consider revealing it.