# MA.2.NSO.2.1

Recall addition facts with sums to 20 and related subtraction facts with automaticity.
General Information
Subject Area: Mathematics (B.E.S.T.)
Strand: Number Sense and Operations
Status: State Board Approved

## Benchmark Instructional Guide

### Terms from the K-12 Glossary

• Automaticity
• Equation
• Expression

### Vertical Alignment

Previous Benchmarks

Next Benchmarks

### Purpose and Instructional Strategies

The purpose of this benchmark is to build students’ automaticity with addition facts with sums to 20 and related subtraction facts. Students in grade 1 worked to recall sums within 10 and the related subtraction facts.
• Instruction focuses on the fact that automaticity is usually the result of repetition and practice.
• Instruction of this benchmark should not be in isolation from other benchmarks that emphasize understanding.
• Instruction should not focus on speed in the classroom.
• Instruction may initially include explicit strategies such as doubles, doubles plus one, making a ten and fact families.
• The correct way to assess automaticity is to observe students within the instructional setting as they complete problems that involve addition and subtraction. Even though such problems can typically be done without automaticity they will be done with less effort with automaticity.

### Common Misconceptions or Errors

• Students may rely heavily on visual representation or manipulatives.

### Strategies to Support Tiered Instruction

• Teacher provides the addition expression 8 + 6 and has students provide the sum. Once they have given the correct sum of 14, teacher asks “Is there another fact with the same sum?” If students are able to provide another addition expression, teacher asks them to find another one and repeats with subtraction expression, 17 – 9. Students should provide the difference of 8. Students may need to use a manipulative to assist in determine the difference. Once students have given the correct difference, teacher asks “Can you give me a related subtraction equation?”
• Example:

• Teacher co-creates a real-world scenario using a set of given numbers: 6, 7, and 13. Once students have helped to develop an appropriate real-world scenario, teacher discusses what might happen with the problem if the scenario is changed to the inverse operation. The teacher may find that students are not creating a true equation from the scenario they shared. Consider discussing how the numbers are related and how they are affected when the inverse operation is used.
• Teacher provides manipulatives like two color counters and asks students to create a representation of 12. Depending on how they represent the number six, the teacher has them separate the counters into two addends. They may have 12 red counters and 0 yellow showing. The equation is 12 + 0 = 12. The teacher asks them how they could create a different representation, but with the same sum. Manipulation of the counters is continued until students can identify all sets of two addends that equal 12.
• Teacher provides a real-world problem using numbers up to 20.
• For example, Gavin has 14 toy cars. His brother takes 6 of his toy cars. How many toy cars does he have now? Students use a manipulative to helps solve the problem. The teacher acts out the scenario with the students, then represents the problem in an equation.

Using any number between 11-20 as the target number, provide students with digit cards 1-9.
• Part A. Have students select a digit card to recall the missing addend needed to make the target number.
• Part B. Work mentally to create an equation that is equal to the target number.

Create two addition equations and two related subtraction equations using only the digits 1, 4, 7, and 3. (Digits can be combined and used more than once.)

### Instructional Items

Instructional Item 1

What subtraction equation can be used to determine the value of 5+13?

a. 19-5 =14
b. 18–5=13
c. 12–8=4
d. 13–5=8

Instructional Item 2

Which of the following addition expressions have a sum of 20?
a. 8 + 12
b. 15 + 4
c. 11 + 9
d. 6 + 13
e. 3 + 7
f. 14+4
g. 10+10

*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive.

## Related Courses

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

## Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.
MA.2.NSO.2.AP.1: Recall addition facts with sums to 10 and related subtraction facts.

## Related Resources

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

## 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

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

Type: Formative Assessment

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

Type: Formative Assessment

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

Type: Formative Assessment

## Lesson Plans

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit PART 3 :

Students will play a fluency game adding within 20 using playing cards.  There will be Responsible/Irresponsible Citizen cards embedded in the deck of cards that will result in an advantage or disadvantage in the game.  This integrated lesson is part 3 of 3 in a mini unit.

Type: Lesson Plan

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit Part 2:

Students will circulate the room to find a partner who has an addend card that equals 20 with their addend card.  The activity will include matching behaviors that are examples of responsible and irresponsible citizenship. This integrated lesson is part 2 of 3 in a mini unit.

Type: Lesson Plan

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit PART 1 :

Students will work in small groups to play a sum game taking turns finding 2 addends that equal a specific number within 20.  Throughout the game, the teacher will be giving students cards representing responsible behaviors that will give an advantage or irresponsible behaviors that will cause a disadvantage.  This integrated lesson is part 1 of 3 in a mini unit.

Type: Lesson Plan

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

## Perspectives Video: Experts

Fluency vs. Automaticity:

How are fluency and automaticity defined? Dr. Lawrence Gray explains fluency and automaticity in the B.E.S.T. mathematics benchmarks in this Expert Perspectives video.

Type: Perspectives Video: Expert

B.E.S.T. Journey:

What roles do exploration, procedural reliability, automaticity, and procedural fluency play in a student's journey through the B.E.S.T. benchmarks? Dr. Lawrence Gray explains the path through the B.E.S.T. mathematics benchmarks in this Expert Perspectives video.

Type: Perspectives Video: Expert

What is Automaticity?:

What does automaticity look like? What is the role of automaticity in mathematics? Dr. Lawrence Gray explores what it means for students to have automaticity with basic mathematics facts in this Expert Perspectives video.

Type: Perspectives Video: Expert

## 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

Students are assessed on a set of basic addition facts 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.