Unit 4

Addition and Subtraction Within 200 with Word Problems to 100

Math

Unit Length and Description:

9 weeks

In Unit 4, students apply their work with place value units to develop conceptual understanding of addition and subtraction within 1000 moving from concrete to pictorial to abstract. Students deepen their understanding of base-ten, place value, and the properties of operations. They apply their knowledge to one-step and two-step word problems. During this unit, students also continue to develop one of the required fluencies of the grade: addition and subtraction within 100.

Standards:

Enduring Understandings:

·         When one quantity is joined or added on to another quantity, the result is greater than or equal to the initial quantity.

•   When one quantity is removed from another quantity, the result is less than or equal to the initial quantity.

·     Joining, removing, part-part-whole, and comparing problems can be modeled.

·     Addition and subtraction can be composed and decomposed to simplify the operation.

·     Mental math strategies may be used to solve problems involving numbers.

·         Problems and solutions can use various representations, including concrete objects, pictures, number sentences, and words.

Essential Questions:

·         How do we use addition and subtraction to tell number stories?

·         How does using ten as a benchmark number help us add and subtract?

·         How can we solve addition problems?

·         How can we solve subtraction problems?

·         How can strategies help us when adding and subtracting?

·         How are addition and subtraction alike and how are they different?

·         How are problem-solving strategies alike and different?