Math Curriculum

Level C
Unit: Number Base Ten (Decimals)
Lesson 6.5.2 Using Diagrams to Represent Addition and Subtraction

Instructor Materials

  • Teacher guide
  • Slides
  • Squares and Rectangles resource
  • Practice Problems resource
  • CCRS standard: 6.NS.3
  • Learning goal: Compare and contrast (orally and in writing) vertical calculations and base-ten diagrams that
    represent adding and subtracting decimals. Explain (in words and through other representations) that adding and subtracting decimals requires combining digits that represent like base-ten units. Interpret and create diagrams that represent 10 like base-ten units being composed into 1 unit of higher place value, e.g., 10 tenths as 1 one, and comprehend the word “bundle” to refer to this concept.
  • 6.5 Assessments and Related Lessons

Student Materials



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