# Lesson 12

Subtract From a Teen Number

### Lesson Purpose

The purpose of this lesson is for students to add and subtract within 20 without composing or decomposing a ten.

### Lesson Narrative

In previous lessons, students learned the 1$$0 + n$$ structure of teen numbers and considered the relationship between addition and subtraction. The purpose of this lesson is for students to use their understanding of the structure of teen numbers to add and subtract from a teen number, without composing or decomposing a ten (MP7). Students use methods they used in a previous section such as counting on, taking away, or relating addition and subtraction.

• Representation
• MLR8

### Learning Goals

Teacher Facing

• Add and subtract single-digit numbers from teen numbers without composing or decomposing a ten.

### Student Facing

• Let’s subtract and add within 20.

### Required Materials

Materials to Gather

Materials to Copy

• Shake and Spill Stage 4 and 5 Recording Sheet (G1 and 2)

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 10 min Activity 3 15 min Lesson Synthesis 10 min Cool-down 0 min

### Teacher Reflection Questions

What connections did students make between the different methods shared? What questions did you ask to help make the connections more visible?

### Print Formatted Materials

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