Unit 4, Lesson 10
Place Value and the Number Line
Grade 2
Preparation
Lesson Narrative
In previous lessons, students matched addition and subtraction equations and their representations on a number line. They found the value of differences within 100 and represented their thinking on a number line.
In this lesson, students add and subtract within 100 and represent computation methods on a number line. They compare representations of methods based on place value and make connections across representations (MP2). The expressions in each activity include numbers that elicit methods based on counting on or counting back by place.
- Representation
- MLR8
- Interpret (orally) base-ten diagrams and number line diagrams that represent place value strategies for addition and subtraction.
- Use a number line to represent addition and subtraction strategies based on place value that do not require composing or decomposing a ten.
- Let’s compare methods using the number line.
Required Preparation
None
Teacher Reflection Questions
Why is it important for students to be able to represent their thinking and strategies using varied representations? How can you support students to feel comfortable using other representations?