Mental MathFact Learning

Mental ComputationEstimation

Grade 1 Teachers Guide

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Table of ContentsMental Math in the Elementary Mathematics Curriculum . . . . . . . . . . . . . 1Definitions and Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Introducing Thinking Strategies to Students . . . . . . . . . . . . . . . . . . . . . . . 8Practice and Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Response Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Timed Tests of Basic Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Parents and Guardians: Partners in Developing Mental Math Skills . . . . 13Pre-operational Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Patterned Set Recognition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Part-Part-Whole Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Ten-Frame Visualization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Other Number Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18One More/One Less and Two More/Two Less . . . . . . . . . . . . . . . 18Next Number and Counting On and Back . . . . . . . . . . . . . . . . . . . 19

Fact Learning - Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Thinking Strategies for Addition Fact Learning . . . . . . . . . . . . . . . . . . . . 22

Doubles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Plus 1 Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Plus 2, Plus 3 Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Using Five-Frames and Ten-Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Model Numbers on a Five-Frame . . . . . . . . . . . . . . . . . . . . . . . . . . 25Visualize Combinations on a Five-Frame . . . . . . . . . . . . . . . . . . . . 26Random Numbers on a Five-Frame . . . . . . . . . . . . . . . . . . . . . . . . 26Ten-Frame Flash Cards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Ten-Frame Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Empty Ten-Frame Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Fact Learning Subtraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Subtraction as Think Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Ten-Frame Visualization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Counting Back . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Subtraction Facts With Minuends to 10 . . . . . . . . . . . . . . . . . . . . . 30

Mental Computation - Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Adding 10 to a Single-Digit Number . . . . . . . . . . . . . . . . . . . . . . . . 32Developing the Concept With 2-Part Mats . . . . . . . . . . . . . . . . . . . 32Developing the Concept With Ten-Frames . . . . . . . . . . . . . . . . . . 33

Appendixes Thinking Strategies in Mental Math . . . . . . . . . . . . . . . . . . . . . . . . 38Scope and Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Mental Math Grade 1 1

Mental Math in the Elementary Mathematics Curriculum

Mental math in this guide refers to fact learning, mental computation, andcomputational estimation. The Atlantic Canada Mathematics Curriculumsupports the acquisition of these skills through the development of thinkingstrategies across grade levels.

Mental math refers to fact learning, mental computation, andcomputational estimation. The Atlantic Canada Mathematics

Curriculum supports the acquisition of these skills through thedevelopment of thinking strategies across grade levels.

Pre-Operational Skills Many children begin school with a limited understanding of number andnumber relationships. Counting skills, which are essential for ordering andcomparing numbers, are an important component in the development ofnumber sense. Counting on, counting back, concepts of more and less,and the ability to recognize patterned sets, all mark advances in childrensdevelopment of number ideas.

Basic facts are mathematical operations for which some studentsmay not be conceptually prepared.

Basic facts are mathematical operations for which some students may notbe conceptually prepared. As a minimum, the following skills should be inplace before children are expected to acquire basic facts.

Students can immediately name the number that comes after a givennumber from 0-9, or before a given number from 2-10.

When shown a familiar arrangement of dots # 10 on ten frames, dice,or dot cards, students can quickly identify the number withoutcounting.

2 Mental Math Grade 1

For numbers # 10 students can quickly name the number that isone-more, one-less; two-more, two-less. (the concept of less tends tobe more problematic for children and is related to strategies for thesubtraction facts)

Mental mathematics must be a consistent partof instruction in computation from primarythrough the elementary and middle grades.

Mental Math Grade 1 3

Curriculum Outcomes Thinking StrategiesGrade 1

B7- use mental strategies to find sumsto 18 and differences from 18 orless

B8- memorize simple addition and/orsubtraction facts from among thosefor which the total is 10 or less

C5- use number patterns to help solveaddition and subtraction sentences

P. 28 Doubles Facts for addition and

subtraction factsP. 36 Using patterns to learn the facts Commutative property (3+2 = 2+3)

Grade 2

B5- develop and apply strategies tolearn addition and subtraction facts

B11- estimate the sum or differenceof two 2-digit numbers

Fact learning is a mentalexercise with an oral and/orvisual prompt; the focus isoral, rather than paper-and

pencil; drills should be shortwith immediate feedback over anextended period of time.

P. 22 Doubles plus 1 Make 10 (bridging to 10) Two-apart facts; double in-between Subtraction as think addition Compensation Balancing for a constant difference

P. 30 (Estimation) Rounding both numbers to the

nearest 10 Round one number up and one

number down Front-end estimation

Grade 3

B11/12- mentally add and subtracttwo-digit and one-digitnumbers, and roundednumbers.

B9- continue to estimate in addition andsubtraction situations

B10- begin to estimate in multiplication and division situations

C3 - use and recognize the patterns in amultiplication table

P. 34 Make 10 Compatible numbers (partner

numbers) Front-end addition Back up through ten (counting on) Compensation Balancing for a constant difference

P. 28 Commutative property for

multiplication (3x2 = 2x3) Division as think multiplication Helping facts

4 Mental Math Grade 1

Curriculum Outcomes Thinking StrategiesGrade 4

B9 - demonstrate a knowledge of themultiplication facts to 9 x 9

B14 - estimate the product or quotient of2- or 3-digit numbers and singledigit numbers

B15 - mentally solve appropriateaddition and subtractioncomputations

B16 - mentally multiply 2-digit numbersby 10 or 100

C2 - apply the pattern identified whenmultiplying by increasing powersof 10

P. 32 Doubles Clock-facts for 5s Patterns for 9s Helping facts

P. 36 (Estimation) Rounding Front-end Clustering of Compatibles

P. 38 Compatibles for division

P. 40 Front-end addition Compensation Up through 100 (counting on) Back down through 100 (counting

back) Compatible numbers Place-value-change strategy for

mentally multiplying by 10, 100

Mental Math Grade 1 5

Curriculum Outcomes Thinking StrategiesGrade 5

B10- estimate sums and differencesinvolving decimals to thousandths

B11- estimate products and quotients oftwo whole numbers

B12- estimate products and quotients ofdecimal numbers by single-digitwhole numbers

B15- multiply whole numbers by 0.1,0.01, and 0.001 mentally

C2- recognize and explain the patternin dividing by 10, 100, 1000 and inmultiplying by 0.1, 0.01 and 0.001

B13- perform appropriate mentalmultiplications with facility

By grade 5, students shouldpossess a variety of strategiesto compute mentally. It is

important to recognize that thesestrategies develop and improveover the years with regular

practice.

P. 40 to 41 (Estimation) Rounding one up, one down Looking for compatibles that make

approximately 10, 100, 1000 Front-end

P. 44 Place-value-change strategy for

mentally multiplying by 10, 100, 1000 Halve-double strategy for

multiplication Front-end multiplication Compensation

P. 46 to 50 Place-value-change strategy for

mentally dividing by 10, 100, 1000 Place-value-change strategy for

mentally multiplying by 0.1, 0.01,0.001

Grade 6

B9- estimate products and quotientsinvolving whole numbers only,whole numbers and decimals, anddecimals only

B10- divide numbers by 0.1, 0.01, and0.001 mentally

C2- use patterns to explore division by0.1, 0.01, and 0.001

B11- calculate sums and differences inrelevant