Types of Angles

• Name acute, right, obtuse, straight, and reflex angles.
• Spot angles on a clock face and in triangles.
• Compare angles using a right-angle checker (corner of a book).

Level 1 — What is an angle?

Two rays meeting at a vertex form an angle. Measure in degrees (°).

Level 2 — Types

Level 3 — Clock angles

Level 4 — Triangle angle fact (intro)

Every triangle's angles add to 180°. If two angles are 60° and 70°, the third = 180 − 130 = 50°.

Indian context: The tip of a dosa on a tawa often forms an acute angle; a fully opened folded newspaper makes a straight angle.

NCERT anchor: Math-Magic 4, Ch 4 — Tick-Tick-Tick (clock angles); Ch 11 — Fields and Fences

Classify 85°, 90°, 110°, 180°

Step 1 — 85° < 90° → **acute**.
Step 2 — 90° → **right**.
Step 3 — 110° between 90° and 180° → **obtuse**.
Step 4 — 180° → **straight**.

At 3 o'clock, what angle do clock hands make?

Step 1 — Hour hand at 3, minute hand at 12.
Step 2 — Quarter turn of a circle = 90°.
Answer: **90° (right angle)**

• Classify 45°, 95°, 180°.
• Clock angle at 9:00?
• Two angles of a triangle are 50° and 60°. Third angle?
• Stretch: Can a triangle have angles 80°, 60°, and 50°? Add them to check. (yes — sum 180°)

Revision tip: Use your book corner as a 90° checker — compare unknown angles to it: smaller = acute, larger = obtuse.

Open the Practice tab for graded questions on Types of Angles.

• Use the platform-native live simulation or PhET-style tool for this topic (number line, Venn, physics playground, molecule builder, sensor dashboard, etc.).
• Mirror / body / home activity: physically do the concept (count objects, measure, role-play) and photograph or describe for portfolio.
• Voice or text reflection with AI Mentor: explain the concept to a younger student or family member.

• "Explain this concept to a Class 6 student using one real example from an Indian home, school, market, or festival."
• "What is one common mistake students make here, and how would you catch yourself making it?"
• Stretch: "How does this connect to coding, robotics, money, health, environment, or a future career?"

• Complete the core practice + one extension activity (photo, table, short reflection, or mini-project) for base XP + topic badge.
• 5-7 day streak or family discussion note = multiplier + visible artifact in parent/principal dashboard.
• Best real-world application stories (anonymised) featured on class or national leaderboard.

• One hands-on project or measurement using the Drishti kit or household items that makes the concept physical.
• Direct link to at least one Future Skill track (Money Management, Green Tech, Cyber Defenders, Micro-Entrepreneurship, AI Mastery, Sustainable Living, Personality Development).
• Coding extension where relevant (simple script, simulation, or data logging).

This material emphasises experiential "learning by doing", competency (apply/create/analyse), vocational exposure, critical thinking, and multidisciplinary connections. Designed to feed live worlds, AI Mentor (with memory), gamification, robotics, parent analytics, and future skills — not just exam prep.

Portfolio Evidence Idea: Your photo/table/reflection/project + one sentence on "How this helps me in real life or a possible future path."

Open the Practice tab for aligned questions (easy/medium/hard + case-based) with full AI scaffolding.

See curriculum for cross-links and the full future-skills/robotics chapters.