# 1.6 Length Measurements Within 120 Units

## Unit Goals

• Students measure length and count up to 120 length units. They solve addition and subtraction story problems with unknowns in all positions.

### Section A Goals

• Compare the lengths of objects indirectly.
• Order objects by length.

### Section B Goals

• Count groups of up to 120 objects and write a number to represent them.
• Lay length units end-to-end with no gaps or overlaps and count the units to determine length.

### Section C Goals

• Solve addition and subtraction story problems with unknowns in all positions.

### Problem 1

#### Pre-unit

Practicing Standards:  K.MD.A.2

1. Circle the rectangle that is longer.
2. Circle the rectangle that is shorter.

### Problem 2

#### Pre-unit

Practicing Standards:  1.OA.A.1

There are 17 fish in Han's aquarium.
There are 9 fish in Clare's aquarium.
How many more fish are in Han’s aquarium than Clare's aquarium?
Show your thinking with drawings, numbers, or words.

### Problem 3

#### Pre-unit

Practicing Standards:  1.NBT.B.2

How many connecting cubes do you see in each picture?

### Problem 4

Use any tool you would like to compare the length of the rectangles.

List the rectangles from longest to shortest.

### Problem 5

Compare the length of the top and side of your workbook.

Use a drawing or words to show which is longer.

### Problem 6

If needed, the table, bookshelf, and desks can be replaced with other objects in the classroom.

1. Which is longer, the teacher's desk or your desk?
Show your thinking using drawings, numbers, or words.
2. Which is shorter, the table or the bookshelf?
Show your thinking using drawings, numbers, or words.

### Problem 7

#### Exploration

Which is farther from your school, your home or your best friend's home? Explain how you know or how you can find out which is farther.

### Problem 8

#### Exploration

Which is farther from your classroom door, the bathroom or the main office? Show your thinking using drawings, numbers, or words.

### Problem 1

Use connecting cubes to measure the length of each rectangle.

### Problem 2

1. Jada says the rectangle is 5 paper clips long.

Do you agree with Jada? Why or why not?

2. Do you think the rectangle is less than 5 paper clips long, 5 paper clips long, or more than 5 paper clips long?
Show your thinking using drawings, number or words.

### Problem 3

Jada and Han measure the rectangle.

Jada says the rectangle is 3 long.

Han says that it is 8 long.

Explain how both Jada and Han can be correct.

### Problem 4

Lin measured the length of a table top using these cubes.

What is the length of the table top?
Show your thinking using drawings, numbers, or words.

### Problem 5

#### Exploration

Mai measured the distance from her classroom to the cafeteria using a broom.
She wrote how many times she used the broom:

• 10
• 10
• 10
• 5
• 10
• 10
• 10
• 10
• 8

How many broom lengths was it from Mai's classroom to the cafeteria?
Show your thinking using drawings, numbers, or words.

### Problem 6

#### Exploration

Priya and Noah want to measure their classroom in steps.
Priya takes 28 steps to cross the room and Noah takes 26 steps.

1. How could Priya and Noah get different measurements?
2. Measure the length of your classroom in steps.

### Problem 1

Lin's foot is 8 cubes long.
Her father's foot is 17 cubes long.
How many cubes shorter is Lin's foot than her father's foot?
Show your thinking using drawings, numbers, words, or equations.

### Problem 2

Priya's friendship bracelet is 11 cubes long.
Han's friendship bracelet is 3 cubes shorter than Priya's friendship bracelet.
How long is Han’s friendship bracelet?
Show your thinking using drawings, numbers, words, or equations.

### Problem 3

Tyler has some beads on a bracelet.
He took 6 beads off to give to Clare.
Now there are 7 beads on Tyler's bracelet.
How many beads were on Tyler's bracelet before he took the beads off?
Show your thinking using drawings, numbers, words, or equations.

### Problem 4

There are 13 players on the soccer field.
Some of their friends come to play.
Now there are 19 players on the soccer field.
Circle the equation that represents the situation.

A: $$13 + 19 = \boxed{\phantom{32}}$$
B: $$13 + \boxed{\phantom{32}} = 19$$
C: $$\boxed{\phantom{32}} - 13 = 19$$

### Problem 5

Kiran and Clare made 13 origami swans together.
How many swans did Clare make?
Show your thinking using drawings, numbers, words, or equations.

### Problem 6

#### Exploration

Andre used these connecting cubes to represent a story problem.

What could Andre's story be?

### Problem 7

#### Exploration

Write a story problem.