School Improvement in Maryland

Gr. K Unit: Understand Addition as Putting Together and Adding TO, and Understand Subtraction as Taking Apart and Taking From

Unit Overview

This unit extends the exploration of addition and subtraction that began in Prekindergarten. Students will represent addition and subtraction in a variety of ways, solve addition and subtraction word problems by using objects or drawings to represent the problem, decompose numbers less than or equal to 10, determine the number needed to add to a given number to equal a total of ten, and fluently add and subtract within 5. This is the first fluency expectation of the Maryland Common Core State Standards.

Essential Questions:

  • Why do I need mathematical operations?
  • How do mathematical operations relate to each other?
  • How do I know which mathematical operation (+, -) to use?
  • How do I know which computational method (mental math, estimation, paper and pencil, and calculator) to use?
  • What is meant by equality in mathematics?
  • How do I know where to begin when solving a problem?
  • How does explaining my process help me to understand a problem’s solution better?
  • How do I decide what strategy will work best in a given problem situation?
  • What do I do when I get stuck?
  • How do I know when a result is reasonable?
  • What is the relationship between solving problems and computation?
  • Why is the ability to solve problems the heart of mathematics?

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: K.OA.A.2

Students use two-color counters to build different combinations for the same number and record the combinations as number sentences.

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: K.OA.A.1

Students listen to word problems and then decide which operation to use when solving it.

CCSC Alignnment: K.OA.A.1

Students use the Part-Part-Total mat and counters to act out the different part of the story in Rooster’s Off to See the World.

CCSC Alignnment: K.OA.A.2

Students use white board, markers, counters, and/or Part-Part-Total Mats to solve problems independently.

CCSC Alignnment: K.OA.A.3

Students use a Ziploc bag and buttons to model decomposing a number into two parts.

CCSC Alignnment: K.OA.A.3

Students use colored bears and a balance scale to model different word problems and solve them.

CCSC Alignnment: K.OA.A.4

Students use bean bags or number cubes and the number line to model different combinations for ten.

CCSC Alignnment: K.OA.A.4

Students use connecting cubes to build shapes that use 10 cubes.

CCSC Alignnment: K.OA.A.4

Students play a game in which one student breaks a tower of ten connecting cubes into two parts, showing only one part to his partner. The partner tells how many cubes are in the hidden part.

CCSC Alignnment: K.OA.A.4

Students match two Ten Frame Cards that equal ten.

CCSC Alignnment: K.OA.A.4

The teacher shows a Ten Frame that shows a number between 0 and 10. The students all hold up the ten frame that shows the number needed to make ten.