Lesson 13

Center Day 2

Lesson Purpose

The purpose of this lesson is for students to add and subtract within 20 and work with two-digit numbers.

Lesson Narrative

In the first activity, students choose between activities that offer practice working with two-digit numbers. In the second activity, students choose an activity to work on adding and subtracting within 20.

Learning Goals

Teacher Facing

  • Add and subtract within 20.
  • Add tens to two-digit numbers.
  • Count and represent a collection.

Student Facing

  • Let’s add and subtract and work with tens and ones.

Required Materials

Materials to Gather

Required Preparation

Activity 1:

  • Gather materials from previous centers:
    • Grab and Count, Stage 2
    • Five in a Row, Stages 1–4
    • Check It Off, Stages 1–3

Activity 2:

  • Gather materials from previous centers:
    • How Close, Stages 1 and 2
    • Number Puzzles, Stages 1 and 2
    • Shake and Spill, Stages 3–5

Lesson Timeline

Warm-up 10 min
Activity 1 20 min
Activity 2 20 min
Lesson Synthesis 10 min

Teacher Reflection Questions

As students worked together today, where did you see evidence of the mathematical community established over the course of the school year?

Print Formatted Materials

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Student Task Statements pdf docx
Lesson Cover Page pdf docx
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Teacher Presentation Materials pdf docx

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