(making 20) Beth had a pack of 20 pencils. The pencils were two different colors. Show all the combinations of pencils she could have that equal 20. Draw pictures and write equations to support your answer.

If you don’t know 9 + 3, how can knowing 10 + 2 help you?

If you don’t know 9 + 8, is there a doubles fact that can help you? How?

(use of strategies) If you don’t know the sum of 8 + 5 (or any other fact), what are some good strategies you can use to help you figure out the answer? (finger counting isn’t appropriate, looking for mental math ideas) Have students think, pair, share ideas. Write all ideas on board for class to see.

(making 10) Meghan wants to have 10 donuts in each box. How many more donuts does she need to put in each of the following boxes? A box with 9 donuts? A box with 8 donuts? A box with 3 donuts?

(doubling) Sherry already has 4 erasers. Now her goal is to collect 20 in all. She got 4 more on Monday and 8 on Tuesday. How many does she have in all? How many more does she need to make her goal?

(halving) Connie and Cheryl are twins. Connie’s hair is twice the length of Cheryl’s hair. Connie has decided that she wants to cut her hair to be the same length as her sister’s. Connie’s hair dresser measured her hair and it is 16 inches long. How long will the twins’ hair be?

About the Math

Instruction in basic facts should focus on making sense, using strategies for remembering facts, and seeing relationships. Students need to understand the relationship of addition and subtraction as well as the commutative property. When students see the relationships such that 3 + 5 = 8 and that 5 + 3 = 8, they lessen the number of facts that need to be learned. Recalling basic facts takes time. Instant recall of the basic facts varies from child to child. The use of timed tests is discouraged as a method of learning. Timed tests are only appropriate after students have indicated that they know the facts. Basic facts allow students to be accurate and efficient in computation and mental math. Essential vocabulary for this standard includes: Doubles, Maketen, Neardoubles, sum, difference, addend, count-on, count-back, thinkaddition, strategy, part, total, subtract, add, pattern, tens, ones, digit, addition, and subtraction(online dictionary,visual mathematics dictionary, HCPSS Vocabulary Cards)

The Illustrative Mathematics tasks below demonstrate expectation for this 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.

Quarter 1Quarter 2Quarter 3Quarter 4Develop fluency toadd and subtract within 20 using mental strategies. By the end of Grade 2, know from memory all sums of two one-digit numbers.Review grade 1 facts: +/- 0, 1, 2; make ten; +/- 10; doubles

Develop fluency toadd and subtract within 20 using mental strategies. By the end of Grade 2, know from memory all sums of two one-digit numbers.Make ten and some more

(i.e. 8 + 5 = 13, 9 + 6 = 15)

Develop fluency toadd and subtract within 20 using mental strategies. By the end of Grade 2, know from memory all sums of two one-digit numbers.Near doubles

(i.e. 5 + 6 = 11, 8 + 7 = 15)

Fluentlyadd and subtract within 20 using mental strategies. By the end of Grade 2, know from memory all sums of two one-digit numbers.All facts

SAW3 ResourcesMake 10 and Some MoreAddition Lesson, Resources, PowerPoint Subtraction Lesson, Resources, PowerPointFact Cards and LogsGamesSAW3 ResourcesNear DoublesAdditionLesson, PowerPoint Subtraction Lesson, Resources, PowerPointFact Cards and LogsGamesSAW3 ResourcesHelping FactsAddition Lesson, Resources, PowerPoint SubtractionLesson, PowerPointFact Cards And LogsGamesIncreasing Rigor

Instruction in basic facts should focus on making sense, using strategies for remembering facts, and seeing relationships. Students need to understand the relationship of addition and subtraction as well as the commutative property. When students see the relationships such that 3 + 5 = 8 and that 5 + 3 = 8, they lessen the number of facts that need to be learned. Recalling basic facts takes time. Instant recall of the basic facts varies from child to child. The use of timed tests is discouraged as a method of learning. Timed tests are only appropriate after students have indicated that they know the facts. Basic facts allow students to be accurate and efficient in computation and mental math. Essential vocabulary for this standard includes:About the MathDoubles,Maketen,Neardoubles,sum,difference,addend,count-on,count-back,thinkaddition,strategy,part,total,subtract,add,pattern,tens,ones,digit,addition, andsubtraction(online dictionary,visual mathematics dictionary, HCPSS Vocabulary Cards)The Illustrative Mathematics tasks below demonstrate expectation for this standard.

Rich Tasks for Multiple Means of Engagement, Expression, and Representation (UDL)LINK TO ADDITIONAL BASIC FACTS ACTIVITIES

Print resources:Mental Math in the Primary GradesPages 3-43

Math Intervention, PreK-2Adding Doubles and Near Doublespg 125-126

Adding Doubles and Near Doubles,pages 125-130

Fact Families, pages 131-136Nimble with Numbers 1-2Pages 33-100

Groundworks Reasoning with NumbersPages 64-72

Navigating through Number and OperationsPark Your Car:Pages 49-51Double Plus or Minus:Pages 62-64Flip Two:Pages 65-67Zooey Lunch:Pages 68-69Roads to Reasoning- Grade 2Double Dessert, page 40Mini lessons for Math PracticePages17-22 and 128-132

SuperSource: Snap Cubes, K-2pages 70-73

Web Resources:Games and CentersLessonsStudent ResourcesVideo SegmentsPrintable Game

printable game

Printable Game

Student Resource Sheet

YouTube: Math with Mr. Almeida

Printable Game

Four in a Row with Near Doubles Version 3

Student Resource Sheet

Magic Star Puzzle

Student Resource Sheet

YouTube: Math with Mr. Almeida

(Cache County Public Schools Utah)

Student Resource Sheet

YouTube: Math with Mr. Almeida

Online Games

(Cache County Public Schools Utah)

Student Resource Sheet

Online Game

(Cache County Public Schools Utah)

Student Resource Sheet

Online Game

Student Resource Sheet

Greg Tang Online Game

Doubles and Making 10

Student Resource Sheet

Student Resource Sheet

Student Resource Sheet

Student Resource Sheet

Student resource Sheet

Student Resource Sheet

Greg Tang Student Resource

Greg Tang Student Resource

Greg Tang Student Game

Greg Tang Student GameMaking 10

Math Read Aloud Task Card

Connecting Children's Literature:Two of Everything

by: Lily Toy Tong

Mrs. Wishy-Washy

by: Joy Cowley

Domino Addition

by: Lynette Long

by: Eve Merriam

Math-erpieces

by: Greg Tang

Ten Flashing Fireflies

by: Philemon Sturges

Ready, Set, HOP!

by: Stuart Murphy

Mouse Count

by: Ellen Stoll Walsh

## Questions/Comments:

Contact John SanGiovanni at jsangiovanni@hcpss.org.