##### Unit Overview

In this unit, students understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. This indicates a strong need for Rigor, which requires students to pursue conceptual understanding, procedural skill and fluency, and application with equal intensity. Students in Grade 1 also determine the unknown whole number in an addition or subtraction equation relating three whole numbers. Students should use objects, pictures, words, and symbols to represent mathematical ideas, and have many opportunities to communicate their thinking. Linking equations to concrete materials, drawings, and other representations of problem situations affords deep and flexible understandings of these building blocks of algebra.

**Essential Questions:**

- Why do I need mathematical operations?
- How do mathematical operations relate to each other?
- How do I decide which representation to use when solving problems (concrete manipulatives, pictures, words, or equations)?
- How do I decide which operation to use in solving a problem?
- What is meant by equality in mathematics?
- How do I know when a result is reasonable?
- What questions can be answered using addition and/or subtraction?
- What are the different models of and models for addition and subtraction?
- What are efficient methods for finding sums and differences?

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

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.

CCSC Alignment: 1.OA.D.8

After hearing the story “Dairy of a Worm”, students work with snap cubes and worm pictures to determine the unknown whole number in an addition or subtraction equation relating to three whole numbers and write an addition or subtraction equation for a given problem.

##### 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.

CCSC Alignnment: 1.OA.D.7

Students write equations based on data collected from the class and then write equations about that data. Students then use a balance scale to see if their equations are true.