LEARN NC

K–12 teaching and learning · from the UNC School of Education

Building Sets of 19 and 20

http://illuminations.nctm.org/LessonDetail.aspx?ID=L552

A lesson plan for Grades K–2 Mathematics

Provider: National Council of Teachers of Mathematics

About this resource

Appropriate grades
K–2
Provider
National Council of Teachers of Mathematics

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In this lesson, one of a seven-part unit from Illuminations titled “Let's Count to 20,” students explore sets of 19 and 20. They count up to 20, construct and decompose sets up to 20, and record the decompositions.

North Carolina Curriculum Alignment

Mathematics (2004)

Grade 1

  • Goal 1: Number and Operations - The learner will read, write, and model whole numbers through 99 and compute with whole numbers.
    • Objective 1.01: Develop number sense for whole numbers through 99.
      • Connect the model, number word, and number using a variety of representations.
      • Use efficient strategies to count the number of objects in a set.
      • Read and write numbers.
      • Compare and order sets and numbers.
      • Build understanding of place value (ones, tens).
      • Estimate quantities fewer than or equal to 100.
      • Recognize equivalence in sets and numbers 1-99.
    • Objective 1.03: Develop fluency with single-digit addition and corresponding differences using strategies such as modeling, composing and decomposing quantities, using doubles, and making tens.

Grade 2

  • Goal 1: Number and Operations - The learner will read, write, model, and compute with whole numbers through 999.
    • Objective 1.01: Develop number sense for whole numbers through 999.
      • Connect model, number word, and number using a variety of representations.
      • Read and write numbers.
      • Compare and order.
      • Rename.
      • Estimate.
      • Use a variety of models to build understanding of place value (ones, tens, hundreds).
    • Objective 1.04: Develop fluency with multi-digit addition and subtraction through 999 using multiple strategies.
      • Strategies for adding and subtracting numbers.
      • Estimation of sums and differences in appropriate situations.
      • Relationships between operations.
    • Objective 1.05: Create and solve problems using strategies such as modeling, composing and decomposing quantities, using doubles, and making tens and hundreds.

Kindergarten

  • Goal 1: Number and Operations - The learner will recognize, model, and write whole numbers through 30.
    • Objective 1.01: Develop number sense for whole numbers through 30.
      • Connect model, number word (orally), and number, using a variety of representations.
      • Count objects in a set.
      • Read and write numerals.
      • Compare and order sets and numbers.
      • Use ordinals (1st-10th).
      • Estimate quantities fewer than or equal to 10.
      • Recognize equivalence in sets and numbers 1-10.
    • Objective 1.03: Solve problems and share solutions to problems in small groups.