• Unit Overview

  • Letter Home
  • Unit Preparation
  • Mathematics in this Unit
  • Assessment in this Unit
  • Key Assessment Opportunities Chart
• Daily Practice and Problems
• Home Practice

• Lesson 1

  • Part 1: Revisiting the Subtraction Strategies Menu for the Facts
  • Part 2: Introduce the Triangle Flash Cards for Subtraction
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 2

  • Part 1: Develop Strategies for Subtraction Problems
  • Part 2: Emphasize Different Subtraction Strategies
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 3

  • Developing the Lesson
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 4

  • Part 1: Subtraction Problems with No Trades
  • Part 2: Subtraction Problems with Trades
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 5

  • Part 1: Connect Base-Ten Pieces to Expanded Form
  • Part 2: Check Subtraction with Addition
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 6

  • Part 1: Recording Subtraction on the Base-Ten Recording Sheet
  • Part 2: Checking for Reasonableness
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 7

  • Part 1: Making Connections Between Strategies
  • Part 2: Common Mistakes in Subtracting
  • Part 3: Introducing the Subtraction Strategies Menu
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 8

  • Before the Lesson
  • Part 1: Explore Subtraction Strategies
  • Part 2: Practicing Subtraction Strategies
  • Part 3: Difference War
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

• Lesson 9

  • Developing the Lesson
  • Summarizing the Lesson
  • Homework and Practice
  • Answer Keys

Lesson 2

Subtraction Seminar

Est. Class Sessions: 2–3

Daily Practice and Problems

X

Teacher Notes

X

Have base-ten pieces readily available.

4 skinnies and 18 bits
3 skinnies and 28 bits
2 skinnies and 38 bits
1 skinny and 48 bits
58 bits

E. More Base-Ten Pieces

Shannon represented the number 58 with five skinnies and eight bits.

How else can you represent this number with base-ten pieces?