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)
Required Preparation
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?