# Gr. 1 Unit: Understand And Apply Properties of Operations and the Relationship Between Addition And Subtraction

**LESSON UNIT**

**LESSON PLANS**

**LESSON SEEDS**

### UNIT OVERVIEW

This unit works with the properties of addition and subtraction, specifically the Commutative Property of addition and the Associative Property of addition to help students see that when they know the solution to one equation, it can lead to an understanding of many other related equations. So by applying these two properties, the student who knows that 8 + 7 = 15 will also immediately know that 7 + 8 = 15 and that 15 – 7 = can be thought of as 15 = 7 + . They will also know that when adding 3 + 8 + 7 + 1, they can add the 3 and 7 to get 10. Then add the 8 and 1 to get 9 and arrive at the total of 19 very efficiently.

**Essential Questions:**

- How is math relevant to me?
- What do numbers convey?
- How can numbers be expressed, ordered, and compared?
- What are the addition properties of whole numbers?
- In what way can numbers be composed and decomposed?
- What are different models of and models for addition and subtraction?
- How do addition and subtraction relate to each other?

A question is essential when it stimulates multi-layered inquiry, provokes deep thought and lively discussion, requires students to consider alternatives and justify their reasoning, encourges re-thinking of big ideas, makes meaningful connections with prior learning, and provides students with opportunities to apply problem-solving skills to authentic situations.

**UNIT LESSON:**

Properties of Operations and the Relationship between Addition and Subtraction

Additional information such as Teachers Notes, Enduring Understandings,Content Emphasis by Cluster, Focus Standards, Possible Student Outcomes, Essential Skills and Knowledge Statements and Clarifications, and Interdisciplinary Connections can be found in this Lesson Unit.

**AVAILABLE MODEL LESSON PLANS**

The lesson plan(s) have been written with specific standards in mind. Each model lesson plan is only a MODEL - one way the lesson could be developed. We have NOT included any references to the timing associated with delivering this model. Each teacher will need to make decisions related ot the timing of the lesson plan based on the learning needs of students in the class. The model lesson plans are designed to generate evidence of student understanding.

This chart indicates one or more lesson plans which have been developed for this unit. Lesson plans are being written and posted on the Curriculum Management System as they are completed. Please check back periodically for additional postings.

Apply Properties of Operations as Strategies to Add and Subtract

CCSC Alignment: 1.OA.B.3-4

Students explore the commutative property and addition combinations to create number sentences that show various ways to arrive at a specific sum They use ten frames to build their model and develop an understanding of addition properties.

**AVAILABLE MODEL LESSON SEEDS**

The lesson seed(s) have been written with specific standards in mind. These suggested activity/activities are not intended to be prescriptive, exhaustive, or sequential; they simply demonstrate how specific content can be used to help students learn the skills described in the standards. Seeds are designed to give teachers ideas for developing their own activities in order to generate evidence of student understanding.

This chart indicates one or more lesson seeds which have been developed for this unit. Lesson seeds are being written and posted on the Curriculum Management System as they are completed. Please check back periodically for additional postings.

Use the Commutative Property to Add Numbers More Efficiently

CCSC Alignnment: 1.OA.B.3

Students explore the Commutative Property and find various combinations for the sum of 12 using two addends.

Use the Number Line to Illustrate the Commutative Property

CCSC Alignnment: 1.OA.B.3

Students record equations for pairs of addends and display the combinations on the number line, modeling the Commutative Property.

Use the Associative Property to Add Three Addends Efficiently

CCSC Alignnment: 1.OA.B.3

Students play a number card game in which they draw three cards, arrange them using the Associative Property, and discuss which order makes it easier to arrive at the correct sum.

Understand Subtraction as an Unknown Addend Problem

CCSC Alignnment: 1.OA.B.3-4

Students use counters, double ten frames, and part-part-whole mats to model the relationship between addition and subtraction and solve problems.