From the latest NCERT edition, Part I contains the following major chapters:

1. Orienting Yourself: The Use of Coordinates
2. Introduction to Linear Polynomials
3. The World of Numbers
4. Algebraic Expressions and Identities
5. I'm Up and Down, and Round and Round
6. Measuring Space: Perimeter and Area
7. Exploring Geometrical Properties
8. Sequences and Progressions

For example, NCERT's official files identify:

• Chapter 1: Orienting Yourself: The Use of Coordinates N
• NCERT
• Chapter 2: Introduction to Linear Polynomials N
• NCERT
• Chapter 3: The World of Numbers N
• NCERT
• Chapter 4: Algebraic expressions/identities material N
• NCERT
• Chapter 5: I'm Up and Down, and Round and Round N
• NCERT
• Chapter 6: Measuring Space: Perimeter and Area N
• NCERT
• Chapter 8 includes sequences. N
• NCERT

🎯 What is different about the new 2026–27 book?

This is not simply the old NCERT Class 9 Mathematics book with a new cover.

The 2026–27 CBSE curriculum has been redesigned around NEP 2020 and NCF-SE 2023. CBSE specifically emphasizes:

• Conceptual understanding
• Logical and critical reasoning
• Problem solving
• Mathematical modelling
• Visualisation
• Mathematical communication
• Computational thinking
• Data analytics
• Real-life applications
• Experiential learning
• Indian contributions to mathematics
• Competency-based assessment

CBSE explicitly says the curriculum moves away from rote learning toward deeper conceptual understanding and reasoning.