- Section A: Decimals with Tenths and Hundredths
- Warm-up: Notice and Wonder: Shaded Grid
- 1.1: Shady Fractions
- 1.2: Ways to Express a Number

- Warm-up: True or False: Equivalent Fractions
- 2.1: Card Sort: Diagrams of Fractions and Decimals
- 2.2: True or Not True?

- Warm-up: Which One Doesn’t Belong: Decimals and Fractions
- 3.1: Points on Number Lines
- 3.2: Decimals Compared

- Warm-up: Estimation Exploration
- 4.1: All in Order
- 4.2: 400-Meter Dash in a Flash

- Warm-up: Number Talk: Sums of Fractions
- 5.1: Order Once, Order Twice
- 5.2: Long Jumps
- Section A Summary
- Section A Practice Problems

- Section B: Place-value Relationships through 1,000,000
- Warm-up: What Do You Know about 1,000?
- 6.1: Build Numbers
- 6.2: What is 10,000?

- 7.1: Count and Write Numbers
- 7.2: Many Thousands

- Warm-up: How Many Do You See?
- 8.1: Lin’s Representation
- 8.2: What Number is Represented?
- 8.3: Build Hundred-thousands

- Warm-up: True or False: Expanded Expressions
- 9.1: Card Sort: Large Numbers
- 9.2: Expand Large Numbers

- Warm-up: Number Talk: Related Numbers
- 10.1: Alike but Not the Same
- 10.2: More and More Money

- Warm-up: Estimation Exploration: What Number Could This Be?
- 11.1: Locate Large Numbers
- 11.2: So Many Numbers, So Little Line
- Section B Summary
- Section B Practice Problems

- Section C: Compare, Order, and Round
- Warm-up: Which One Doesn’t Belong: Friendly Numbers
- 12.1: Which is Greater?
- 12.2: Incomplete Numbers
- 12.3: Is It Possible?

- Warm-up: True or False: Decomposed Numbers
- 13.1: Ways to Compare
- 13.2: Video Game Scores

- 14.1: On Which Line Do They Belong?
- 14.2: Closer to Some Multiple

- Warm-up: Estimation Exploration: What Could It Be?
- 15.1: Closer to This or That?
- 15.2: Closer to Which Number?
- 15.3: What’s the Nearest Multiple?

- Warm-up: Number Talk: Missing Numbers
- 16.1: Round to What?
- 16.2: Some Numbers to Round
- 16.3: Rounded Populations

- Warm-up: Notice and Wonder: Plane Altitudes
- 17.1: Apart in the Air
- 17.2: Safe or Unsafe?
- 17.3: No-phone Zone?
- Section C Summary
- Section C Practice Problems

- Section D: Add and Subtract
- Warm-up: Estimation Exploration: What’s the Difference?
- 18.1: Weekly Steps
- 18.2: Steps During the Weekend

- Warm-up: Number Talk: Subtract Fractions
- 19.1: Find and Check Sums
- 19.2: Priya’s Family Heirlooms

- Warm-up: Notice and Wonder: Subtracting Tens of Thousands
- 20.1: Add and Subtract Large Numbers
- 20.2: Spot Errors

- Warm-up: Which One Doesn’t Belong: Numbers with 0, 2, and 5
- 21.1: What If There is Nothing to Decompose?
- 21.2: What is Your Age?

- Warm-up: True or False: Sums and Differences
- 22.1: The Fundraiser
- 22.2: The Least and the Greatest of Them All
- Section D Summary

- Warm-up: Estimation Exploration: Bees
- 23.1: Termites, Ants, and Bees
- 23.2: Bee Population
- Section D Practice Problems

- Glossary
- Image Attributions

- Citations
- Notes
- Notes