Topics
Number System (Including Estimation and Approximation)
Number System
Theme 1 : Numbers
Number System(Consolidating the Sense of Numberness)
Ratio and Proportion
Theme 2 : Ratio, Proportion and Arithmetic Problems
Numbers in Indian and International Systems (With Comparison)
Estimation
Theme 3 : Algebra
Numbers in India and International System (With Comparison)
Algebra
Natural Numbers and Whole Numbers (Including Number Line and Patterns)
Place Value
Negative Numbers and Integers
Geometry
Theme 4 : Geometry
Mensuration
Theme 5 : Mensuration
Sets
Natural Numbers and Whole Numbers (Including Patterns)
Negative Numbers and Integers
Theme 6 : Statistics
Data Handling
Fractions
Number Line
Decimal Fractions
Playing with Numbers (Including H.C.F. and L.C.M.)
HCF and LCM
Playing with Numbers
- Simplification of Brackets
- Finding Factors Using Rectangular Arrangements and Division
- Factors and Common Factors
- Multiples and Common Multiples
- Concept of Even and Odd Number
- Tests for Divisibility of Numbers
- Divisibility by 2
- Divisibility by 4
- Divisibility by 8
- Divisibility by 3
- Divisibility by 6
- Divisibility by 9
- Divisibility by 5
- Divisibility by 11
Ratio and Proportion (Including Unitary Method)
Sets
Percent (Percentage)
Idea of Speed, Distance and Time
Ratio
Fundamental Concepts (With operations on Algebraic Expressions)
Proportion (Including Word Problems)
Unitary Method
Framing Algebraic Expressions (Including Substitution and Linear Equations)
Fundamental Concepts (Including Angles and their Properties)
Fractions
- Concept of Fraction
- Types of Fractions
- Concept of Proper and Improper Fractions
- Concept of Mixed Fractions
- Like and Unlike Fraction
- Concept of Equivalent Fractions
- Conversion between Improper and Mixed fraction
- Conversion between Unlike and Like Fractions
- Simplest Form of a Fractions
- Comparing Fractions
- Addition of Fraction
- Subtraction of Fraction
- Multiplication of Fraction
- Division of Fractions
- Using Operator 'Of' with Multiplication and Division
- BODMAS Rule
- Problems Based on Fraction
Decimal Fractions
Triangles (Including Types and Properties of Triangles)
Quadrilaterals
Percent (Percentage)
Circles
Idea of Speed, Distance and Time
Symmetry
Fundamental Concepts
Constructions
Fundamental Operations (Related to Algebraic Expressions)
Substitution (Including Use of Brackets as Grouping Symbols)
Recognition of Solids
Framing Algebraic Expressions (Including Evaluation)
Perimeter and Area of Plane Figures
Data Handling (Including Mean and Median)
Simple (Linear) Equations (Including Word Problems)
Fundamental Concepts
Angles (With Their Types)
Properties of Angles and Lines (Including Parallel Lines)
Triangles (Including Types, Properties and Constructions)
Quadrilateral
Polygons
The Circle
Symmetry (Including Constructions on Symmetry)
Recognition of Solids
Perimeter and Area of Plane Figures
Data Handling (Including Pictograph and Bar Graph)
Mean and Median
Estimated time: 11 minutes
- Definition: Interior of an Angle
- Definition: Exterior of an Angle
- Angle Formation by Rotation
- Formation of Different Angles
CISCE: Class 6
Definition: Interior of an Angle
The interior of an angle is defined as the region or planar area that lies between the two rays (or "arms") that form the angle.

CISCE: Class 6
Definition: Exterior of an Angle
The interior of an angle is the region or planar area that lies between the two rays (or arms) that form the angle.
CISCE: Class 6
Angle Formation by Rotation
1. Starting Point
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Take a ray OA (a line that starts at point O and goes in one direction).
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Point O is called the vertex, and OA is the initial position of the ray.

2. Rotating the Ray
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Now imagine the ray OA is rotating around its fixed endpoint O.
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As it turns, it takes a new position — let’s call the new ray OA′.

3. Forming the Angle
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The amount of turning or rotation between the initial position OA and the new position OA′ is called an angle.
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This angle is written as ∠AOA′.
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The space between OA and OA′ is the interior of the angle.

CISCE: Class 6
Formation of Different Angles
| Illustration | Measure / Range | Illustration | Measure / Range |
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Acute angle (< 90°) | ![]() |
Right angle (90°) |
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Obtuse angle (> 90° but < 180°) | ![]() |
Straight angle (180°) |
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Reflex angle (> 180° but < 360°) | ![]() |
Three-right angles or 270° |
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Angle close to 360° (Reflex angle) | ![]() |
Complete angle (360°) |








