Grade 3Think Math! is founded upon the principle that children are curious problem solvers. Each grade level’s content builds a puzzler’s disposition, developing mathematical “habits of mind” through games, puzzles, mental math, and other collaborative activities – with the goal of providing engaging and motivating experiences for a community of diverse learners.

In Think Math!, third graders use visual models, including arrays and intersections, to build a foundational understanding of multiplication. Starting with smaller models (e.g. 3 × 5 array array or 12 intersections intersections ) and eventually moving to larger models (e.g., 12 × 11 array), children use partitioning as strategy for decomposing into smaller parts. They investigate division as “undoing” multiplication – and relate multiplication to area (while also experimenting with perimeter). Fractional understanding, including naming fractions, making equivalent fractions, and comparing fractions by size and location on the number line, is also explored (and further developed in grades 4 and 5).

All student materials can be accessed through the table below as PDFs by chapter.

Chapter Listing

Chapter Topics Think Math! Resources
Chapter 1: Building Operations
  • Working with addition, subtraction, and fact families
  • Skip-counting and number patterns
Chapter 1 Student Lesson Activity (LAB) pages

Chapter 1 Student Handbook pages Chapter 1 Practice pages Chapter 1 Extension pages Chapter 1 Activity Masters

Chapter 1 School-Home Connection Letter (English/Spanish)

Chapter 2: Multiplication Situations
  • Using visual models to understand multiplication


Chapter 2 Student Lesson Activity (LAB) pages

Chapter 2 Student Handbook pages Chapter 2 Practice pages Chapter 2 Extension pages Chapter 2 Activity Masters

Chapter 2 School-Home Connection Letter (English/Spanish)

Chapter 3: Using Addition and Subtraction
  • Building computational fluency and accuracy
  • Reasoning about addition and subtraction problems
  • Regrouping
  • Estimating


Chapter 3 Student Lesson Activity (LAB) pages

Chapter 3 Student Handbook pages Chapter 3 Practice pages Chapter 3 Extension pages Chapter 3 Activity Masters

Chapter 3 School-Home Connection Letter (English/Spanish)

Chapter 4: Grouping, Regrouping, and Place Value
  • Grouping measurement units
  • Place value
Chapter 4 Student Lesson Activity (LAB) pages

Chapter 4 Student Handbook pages Chapter 4 Practice pages Chapter 4 Extension pages Chapter 4 Activity Masters

Chapter 4 School-Home Connection Letter (English/Spanish)

Chapter 5: Understanding Addition and Subtraction Algorithms
  • Rounding and estimating
  • Using mental computation
  • Place value
Chapter 5 Student Lesson Activity (LAB) pages

Chapter 5 Student Handbook pages Chapter 5 Practice pages Chapter 5 Extension pages Chapter 5 Activity Masters

Chapter 5 School-Home Connection Letter (English/Spanish)

Chapter 6: Rules and Patterns
  • Developing algebraic thinking
  • Graphs and tables
Chapter 6 Student Lesson Activity (LAB) pages

Chapter 6 Student Handbook pages Chapter 6 Practice pages Chapter 6 Extension pages Chapter 6 Activity Masters

Chapter 6 School-Home Connection Letter (English/Spanish)

Chapter 7: Fractions
  • Reasoning about fractions
  • Making equivalent fractions
  • Comparing fractions


Chapter 7 Student Lesson Activity (LAB) pages

Chapter 7 Student Handbook pages Chapter 7 Practice pages Chapter 7 Extension pages Chapter 7 Activity Masters

Chapter 7 School-Home Connection Letter (English/Spanish)

Chapter 8: Charts and Graphs
  • Collecting information
  • Decision-making about how to organize and display information


Chapter 8 Student Lesson Activity (LAB) pages

Chapter 8 Student Handbook pages Chapter 8 Practice pages Chapter 8 Extension pages Chapter 8 Activity Masters

Chapter 8 School-Home Connection Letter (English/Spanish)

Chapter 9: Exploring Multiplication
  • Supporting knowledge of multiplication facts
  • Partitioning rectangular arrays
Chapter 9 Student Lesson Activity (LAB) pages

Chapter 9 Student Handbook pages Chapter 9 Practice pages Chapter 9 Extension pages Chapter 9 Activity Masters

Chapter 9 School-Home Connection Letter (English/Spanish)

Chapter 10: Length, Area, and Volume
  • Distinguishing among different dimensions
  • Estimating measurements
  • Reasons for measurement
  • Considering area and perimeter together
Chapter 10 Student Lesson Activity (LAB) pages

Chapter 10 Student Handbook pages Chapter 10 Practice pages Chapter 10 Extension pages Chapter 10 Activity Masters

Chapter 10 School-Home Connection Letter (English/Spanish)

Chapter 11: Geometry
  • Two-dimensional geometry
  • Three-dimensional geometry
Chapter 11 Student Lesson Activity (LAB) pages

Chapter 11 Student Handbook pages Chapter 11 Practice pages Chapter 11 Extension pages Chapter 11 Activity Masters

Chapter 11 School-Home Connection Letter (English/Spanish)

Chapter 12: Multiplication Strategies
  • Partitioning arrays to multiply two-digit numbers
  • Relating multiplication and division
Chapter 12 Student Lesson Activity (LAB) pages

Chapter 12 Student Handbook pages Chapter 12 Practice pages Chapter 12 Extension pages Chapter 12 Activity Masters

Chapter 12 School-Home Connection Letter (English/Spanish)

Chapter 13: Time, Temperature, Weight, and Capacity
  • Choosing an appropriate and/or unit
  • Reading measurement tools
  • Developing benchmark values
Chapter 13 Student Lesson Activity (LAB) pages

Chapter 13 Student Handbook pages Chapter 13 Practice pages Chapter 13 Extension pages Chapter 13 Activity Masters

Chapter 13 School-Home Connection Letter (English/Spanish)

Chapter 14: Addition and Subtraction in Depth
  • Expanded notation


Chapter 14 Student Lesson Activity (LAB) pages

Chapter 14 Student Handbook pages Chapter 14 Practice pages Chapter 14 Extension pages Chapter 14 Activity Masters

Chapter 14 School-Home Connection Letter (English/Spanish)

Chapter 15: Multiplication and Division
  • Properties of multiplication and division
  • Relating multiplication and division
Chapter 15 Student Lesson Activity (LAB) pages

Chapter 15 Student Handbook pages Chapter 15 Practice pages Chapter 15 Extension pages Chapter 15 Activity Masters

Chapter 15 School-Home Connection Letter (English/Spanish)