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Grade 1
Subtraction (1 to 20)
Subtraction Strategies
Subtracting Doubles Minus 1
Grade 1
1.
Shapes and Solids Around Us
1.1.
Longer and Shorter
1.2.
Longest and Shortest
1.3.
Bigger and Smaller
1.4.
Biggest and Smallest
1.5.
Taller and Shorter
1.6.
Tallest and Shortest
1.7.
Thicker and Thinner
1.8.
Thickest and Thinnest
1.9.
Heavier and Lighter
1.10.
Heaviest and Lightest
1.11.
Near and Far
1.12.
More and Less
1.13.
Nearest and Farthest
2.
Spatial Understanding
2.1.
Top and Bottom
2.2.
On and Under
2.3.
Above and Below
2.4.
Inside and Outside
2.5.
Left and Right
2.6.
Front and Behind
2.7.
Open and Closed
2.8.
Before and After
3.
Numbers from 1 to 10
3.1.
Counting Numbers
3.2.
Number Names
3.3.
Comparing Numbers
3.3.1.
By Counting the Number of Objects
3.3.2.
By Counting the Number of Beads on the Abacus
3.3.3.
By Using Number Line
3.4.
Ascending and Descending Order
3.5.
Before, After, and Between
3.5.1.
By Using Number Line
3.5.2.
By Counting Forward and Backward
3.6.
Ordinal Numbers
3.7.
Number Combinations
3.7.1.
To form the Number 1
3.7.2.
To form the Number 2
3.7.3.
To form the Number 3
3.7.4.
To form the Number 4
3.7.5.
To form the Number 5
3.7.6.
To form the Number 6
3.7.7.
To form the Number 7
3.7.8.
To form the Number 8
3.7.9.
To form the Number 9
3.7.10.
To form the Number 10
4.
Numbers from 11 to 20
4.1.
Counting Numbers
4.2.
Number Names
4.3.
Comparing Numbers
4.3.1.
By Counting the Number of Beads on the Abacus
4.3.2.
By Using Number Line
4.4.
Ascending and Descending Order
4.5.
Before, After, and Between
4.5.1.
By Using Number Line
4.5.2.
By Counting Forward and Backward
5.
Numbers from 21 to 100
5.1.
Counting Numbers from 21 to 100
5.1.1.
Counting Numbers from 20 to 29
5.1.2.
Counting Numbers from 30 to 39
5.1.3.
Counting Numbers from 40 to 49
5.1.4.
Counting Numbers from 50 to 59
5.1.5.
Counting Numbers from 60 to 69
5.1.6.
Counting Numbers from 70 to 79
5.1.7.
Counting Numbers from 80 to 89
5.1.8.
Counting Numbers from 90 to 100
6.
Numbers from 1 to 100
6.1.
Complete the Number Grid from 1 to 100
6.2.
Fill in the Missing Numerals
6.3.
Counting up to 100 by Grouping in Tens
6.4.
Place Value
6.4.1.
Place Value Models up to 100
6.4.2.
Identifying the Number at Ones and Tens Place
6.5.
Number and Number Names up to 100
6.6.
Reading Numbers on Abacus
6.7.
Expanded Form
6.7.1.
Numerals in Expanded Form
6.7.2.
Numerals in Short Form
6.8.
Identifying One-Digit and Two-Digit Numbers
6.9.
Comparing Numbers
6.9.1.
Comparing Numbers on a Number Line
6.9.2.
Comparing Numbers Using the Rules of Comparison
6.9.3.
Ascending and Descending Order
6.9.4.
Find the Greatest Number
6.9.5.
Find the Smallest Number
6.10.
Before, After and Between up to 100
6.10.1.
Before, After and Between Using Number Line
6.11.
Estimate Without Counting to the Nearest Ten
6.12.
Counting Numbers
7.
Addition (1 to 20)
7.1.
Addition of Two Numbers
7.1.1.
Addition by Counting the Number of Objects
7.1.2.
Addition by Counting the Number of Lines
7.1.3.
Addition by Counting on Fingers
7.1.4.
Addition on a Number Line (1 to 10)
7.1.5.
Addition on a Number Line (11 to 20)
7.2.
Addition of Three Numbers
7.2.1.
Addition by Counting the Number of Lines
7.2.2.
Addition to Make 10
7.3.
Addition Sentences
7.3.1.
Write Addition Sentences by Counting the Number of Objects
7.3.2.
Identify the Correct Sum
7.3.3.
Related Addition Facts
7.4.
Add and Compare
7.5.
Addition Skill Builder
7.5.1.
Adding 1
7.5.2.
Adding 2
7.5.3.
Adding 3
7.5.4.
Adding 4
7.5.5.
Adding 5
7.5.6.
Adding 6
7.5.7.
Adding 7
7.5.8.
Adding 8
7.5.9.
Adding 9
7.6.
Addition of Zero
7.7.
Addition Strategies
7.7.1.
Adding Doubles
7.7.2.
Adding Doubles Plus 1
7.7.3.
Adding Doubles Minus 1
7.7.4.
Adding 3 Numbers Using Doubles Facts
7.8.
Word Problems on Addition
7.9.
Addition to Make 20
8.
Subtraction (1 to 20)
8.1.
Subtraction of Two Numbers
8.1.1.
Subtraction by Counting Backwards
8.1.2.
Subtraction by Drawing Lines and Crossing Them
8.1.3.
Subtraction by Counting the Number of Objects
8.1.4.
Subtraction on a Number Line (1 to 10)
8.1.5.
Subtraction on a Number Line (11 to 20)
8.1.6.
Subtraction by Crossing Out
8.2.
Subtraction Sentences
8.2.1.
Write Subtraction Sentences by Counting the Number of Objects
8.2.2.
Identify Correct Subtraction Sentences
8.2.3.
Related Subtraction Facts
8.3.
Subtract and Compare
8.4.
Subtraction Skill Builder
8.4.1.
Subtracting 1
8.4.2.
Subtracting 2
8.4.3.
Subtracting 3
8.4.4.
Subtracting 4
8.4.5.
Subtracting 5
8.4.6.
Subtracting 6
8.4.7.
Subtracting 7
8.4.8.
Subtracting 8
8.4.9.
Subtracting 9
8.4.10.
Subtraction From 10
8.4.11.
Subtraction From 20
8.5.
Subtraction of Zero
8.6.
Subtraction Strategies
8.6.1.
Subtracting Doubles
8.6.2.
Subtracting Doubles Plus 1
8.6.3.
Subtracting Doubles Minus 1
8.7.
Word Problems on Subtraction
9.
Addition and Subtraction (1 to 20)
9.1.
Relate Subtraction and Addition Facts
9.2.
Choose the Correct Operation to Fill in the Blank
10.
Addition and Subtraction of Numbers up to 100
10.1.
Addition
10.1.1.
Addition Using Place Value Models
10.1.2.
Column Addition
10.1.2.1.
Add a One-Digit Number to a Two-Digit Number
10.1.2.1.1.
Add a One-Digit Number to a Two-Digit Number (Without Carrying)
10.1.2.1.2.
Add a One-Digit Number to a Two-Digit Number (With Carrying)
10.1.2.2.
Add Two Two-Digit Numbers
10.1.2.2.1.
Add Two Two-Digit Numbers (Without Carrying)
10.1.2.2.2.
Add Two Two-Digit Numbers (With Carrying)
10.1.2.3.
Word Problems: Add Two Two-Digit Numbers
10.1.2.3.1.
Word Problems: Add Two Two-Digit Numbers (Without Carrying)
10.1.2.3.2.
Word Problems: Add Two Two-Digit Numbers (With Carrying)
10.2.
Subtraction
10.2.1.
Subtraction Using Place Value Models
10.2.2.
Column Subtraction
10.2.2.1.
Subtract a One-Digit Number from a Two-Digit Number
10.2.2.1.1.
Subtract a One-Digit Number from a Two-Digit Number (Without Borrowing)
10.2.2.1.2.
Subtract a One-Digit Number from a Two-Digit Number (With Borrowing)
10.2.2.2.
Subtract Two Two-Digit Numbers
10.2.2.2.1.
Subtract Two Two-Digit Numbers (Without Borrowing)
10.2.2.2.2.
Subtract Two Two-Digit Numbers (With Borrowing)
10.2.2.3.
Word Problems: Subtract Two Two-Digit Numbers
10.2.2.3.1.
Word Problems: Subtract Two Two-Digit Numbers (Without Borrowing)
10.2.2.3.2.
Word Problems: Subtract Two Two-Digit Numbers (With Borrowing)
11.
Multiplication
11.1.
Multiplication by Repeated addition
11.2.
Multiplication as Equal Grouping
11.3.
Multiplication Tables from 2 to 5
12.
Skip Counting
12.1.
Skip Counting by 2
12.2.
Skip Counting by 3
12.3.
Skip Counting by 4
12.4.
Skip Counting by 5
12.5.
Skip Counting by 6
12.6.
Skip Counting by 7
12.7.
Skip Counting by 8
12.8.
Skip Counting by 9
12.9.
Skip Counting by 10
13.
Patterns and Shapes
13.1.
Patterns
13.1.1.
Introduction to Pattern
13.1.2.
Pattern in Alphabets
13.1.3.
Pattern in Shapes
13.1.4.
Pattern in Numerals
13.1.5.
Odd One Out
13.2.
Shapes
13.2.1.
Plane Shapes (2-D shapes)
13.2.1.1.
Open and Closed Shapes
13.2.1.2.
Identify Different Plane Shapes (Rectangle, Square, Circle, and Triangle)
13.2.1.3.
Count the Vertices and Sides of a Plane Shape
13.2.1.4.
Compare Vertices and Sides of Different Plane Shapes
13.2.1.5.
Visualize a Shape After Flipping, Turning and Sliding It
13.2.2.
Solid Shapes (3-D shapes)
13.2.2.1.
Identify Different Solid Shapes (Cuboid, Cube, Cone, Cylinder, and Sphere)
13.2.2.2.
Solid Shapes Around Us
13.2.2.3.
Count the Vertices, Edges and Faces of Solid Objects
13.2.2.4.
Compare the Vertices, Edges and Faces of Different Solid Objects
13.2.2.5.
Identify Sliding and Rolling Objects
13.2.3.
Differentiate Between 2-D and 3-D Shapes
14.
Time
14.1.
Concept of Day and Night
14.2.
Parts of the Day(Morning, Evening, Noon, and Night)
14.3.
Use of 'AM' and 'PM'
14.4.
Clock
14.4.1.
Basic Facts About Clocks and Time
14.4.2.
Reading Time on the Clock (Interval of an Hour)
14.5.
Calendar
14.5.1.
Days of the Week
14.5.2.
Months of the Year
14.5.3.
Reading a Calendar
14.5.4.
Seasons of the Year
15.
Probability
15.1.
More, Less and Equal Likely Events
15.2.
Certain, Likely, Unlikely, and Impossible Events
16.
Data Handling
16.1.
Counting the Number of Shapes in a Picture
Grade 1 Sri Lanka School Math
Subtracting Doubles Minus 1
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Subtraction Strategies
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