Lesson 2 Relate Counting to Addition

    • Let’s add within 10.

Warm-up Number Talk: 2 or 3 More

Find the value of each expression mentally.

Activity 1 More Shake and Spill

cup turned so two-color counters are spilling out
  1. Priya is playing Shake and Spill.
    She spills 7 red counters and 2 yellow counters.
    How many counters did she spill in all?
    Show your thinking using drawings, numbers, or words.

    Equation:

  2. Tyler spills 5 red counters and 3 yellow counters.
    How many counters did he spill in all?
    Show your thinking using drawings, numbers, or words.

    Equation:

  3. Clare spills 2 red counters and 8 yellow counters.
    How many counters did she spill in all?
    Show your thinking using drawings, numbers, or words.

    Equation:

  4. Han spills 3 red counters and 6 yellow counters.
    How many counters did he spill in all?
    Show your thinking using drawings, numbers, or words.

    Equation:

Activity 2 Are They Both Right?

Kiran and Clare are finding the value of .

Kiran counted on from 2.

Two-color counters. Red, 2. Yellow counters, 7, with labels 3, 4, 5, 6, 7, 8, 9.

 2 + 7 = \boxed{9}

Clare counted on from 7.

Two-color counters, 2 groups. Yellow, 7 counters. Red counters, 2, with labels 8, 9.

7 + 2 = \boxed{9}

How can both methods be correct?
Show your thinking using drawings, numbers, or words.

Activity 3 Practice Addition Within 10

Find the value of each sum.

Practice Problem

Problem 1

Find the value of each sum.