MAFS.2.OA.2.2Archived Standard

Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.
General Information
Subject Area: Mathematics
Grade: 2
Domain-Subdomain: Operations and Algebraic Thinking
Cluster: Level 1: Recall
Cluster: Add and subtract within 20. (Major Cluster) -

Clusters should not be sorted from Major to Supporting and then taught in that order. To do so would strip the coherence of the mathematical ideas and miss the opportunity to enhance the major work of the grade with the supporting clusters.

Date Adopted or Revised: 02/14
Content Complexity Rating: Level 1: Recall - More Information
Date of Last Rating: 02/14
Status: State Board Approved - Archived

Related Courses

This benchmark is part of these courses.
5012040: Grade Two Mathematics (Specifically in versions: 2014 - 2015, 2015 - 2022, 2022 - 2024, 2024 and beyond (current))
7712030: Access Mathematics Grade 2 (Specifically in versions: 2014 - 2015, 2015 - 2018, 2018 - 2022, 2022 and beyond (current))
5020090: STEM Lab Grade 2 (Specifically in versions: 2016 - 2022, 2022 - 2024, 2024 and beyond (current))
5012005: Foundational Skills in Mathematics K-2 (Specifically in versions: 2019 - 2022, 2022 - 2024, 2024 and beyond (current))

Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.

Related Resources

Vetted resources educators can use to teach the concepts and skills in this benchmark.

Educational Games

Number Facts Bingo:

This Flash applet generates number fact questions for the game of Bingo. Each of the six levels focuses on a different range of number facts (addition, subtraction, and multiplication), which are displayed one at a time in a variety of question formats. The applet is intended for use in a class/group setting with a projector or interactive whiteboard. Downloadable cards for each level are available from the menu page. At any time in a game the "number facts so far" feature will reveal all the questions presented in the current round to facilitate review or verification of a winning board.

Type: Educational Game

Practicing Logic with addition and subtraction:

Students are to guess two numbers based on their sum and difference: The sum of 2 numbers is 15 and their difference is 1. What are the 2 numbers?

Type: Educational Game

Formative Assessments

Fluency for Subtraction Within 20:

Students are asked to solve six subtraction within 20 problems and to explain their strategies for solving each problem.

Type: Formative Assessment

Fluency for Addition Within 20:

Students are asked to solve six addition within 20 problems and to explain their strategies for solving each problem.

Type: Formative Assessment

Fluency with Basic Addition Facts:

Students are assessed on their fluency with addition facts within 20.

Type: Formative Assessment

Addition Facts from Memory:

Students are assessed on a set of basic addition facts within 20.

Type: Formative Assessment

Instructional Technique

Video: Differentiating in Math Using Computer Games:

This video show a teacher using a variety of tools and software programs to help the students have a better understanding of math. By incorporating technology in the classroom, the teacher can spend time with students who struggle to understand the concept while others can continue to pass levels in the games to move on to the next concept.

Type: Instructional Technique

Lesson Plans

Give A Cheer MEA!:

In this Model Eliciting Activity, MEA, The Give A Cheer Yearbook Committee needs the students' assistance to determine the best company to purchase the school yearbooks. Students will need to consider the cost, tax, and delivery time in their decision. In a “twist,” students are given additional information about shipping cost and are asked to determine if their procedure for ranking should change.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx


Type: Lesson Plan

Show It Another Way:

In this lesson, students will apply properties of addition in order to add three whole numbers. Students will then decompose the sum using tens and ones.

Type: Lesson Plan

Piece of Cake Mental Math!:

In this lesson, you will find activities that you can use to enable student learning and application of mental math addition (using the make a ten strategy) without using rote memorization.

Type: Lesson Plan

Teaching Idea

Fact of the Day:

This article proposes a structured set of lively, brief, daily exercises designed to help children master number facts and mental math skills. Each day's practice focuses on a small, highly focused, manageable, and strategically selected set of facts or skills that builds directly on the previous days' learning. Related resources (Practice and videos) are cataloged separately.

Type: Teaching Idea

STEM Lessons - Model Eliciting Activity

Give A Cheer MEA!:

In this Model Eliciting Activity, MEA, The Give A Cheer Yearbook Committee needs the students' assistance to determine the best company to purchase the school yearbooks. Students will need to consider the cost, tax, and delivery time in their decision. In a “twist,” students are given additional information about shipping cost and are asked to determine if their procedure for ranking should change.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx


MFAS Formative Assessments

Addition Facts from Memory:

Students are assessed on a set of basic addition facts within 20.

Fluency for Addition Within 20:

Students are asked to solve six addition within 20 problems and to explain their strategies for solving each problem.

Fluency for Subtraction Within 20:

Students are asked to solve six subtraction within 20 problems and to explain their strategies for solving each problem.

Fluency with Basic Addition Facts:

Students are assessed on their fluency with addition facts within 20.

Student Resources

Vetted resources students can use to learn the concepts and skills in this benchmark.

Educational Game

Practicing Logic with addition and subtraction:

Students are to guess two numbers based on their sum and difference: The sum of 2 numbers is 15 and their difference is 1. What are the 2 numbers?

Type: Educational Game

Parent Resources

Vetted resources caregivers can use to help students learn the concepts and skills in this benchmark.

Educational Game

Practicing Logic with addition and subtraction:

Students are to guess two numbers based on their sum and difference: The sum of 2 numbers is 15 and their difference is 1. What are the 2 numbers?

Type: Educational Game