Mathematics
Numbers, shapes, patterns and data — and the reasoning that connects them.
NumbersFactors and multiplesPatternsGeometryMeasurementData handling
12 topics ready
A free library of connected ideas
What are you curious about?
Curiosity is a library of big ideas for children — each one opened five times over, from a first look to the deep end.
Pick a question. Explore it. Go deeper when you want to, and follow a connection when something catches your eye. No grades, no levels — every depth is open to you.
Start with a question
- What is inside you, and where exactly does it all sit?Anatomy of the human body
- How much does a door turn when it opens — and how do we measure a turn?Angles
- No organ works alone — so how does a mouthful of roti reach your toes as energy?Body systems and how they connect
- What is a typical value — and how can one number summarise a whole class?Data handling
Five depths, one idea
How depth works here
Depths belong to topics, not to people. Start anywhere — including the deepest layer — and move back whenever you like.
Depth 1
Discover
Meet the idea through a question and a picture.
Depth 2
Understand
How and why it works — and common mix-ups.
Depth 3
Investigate
Change things, predict and test.
Depth 4
Go deeper
Mechanisms, reasoning and calculations.
Depth 5
Extend
Projects, harder problems, open questions.
Shelves
Browse by subject
Physics
Light, sound, forces, energy and electricity — how the physical world behaves.
LightSoundForces and motionElectricity and magnetism
6 topics ready
Earth and space
Our planet, its oceans and skies, and the Sun and Moon that move them.
Sun, Moon and skyOceans
3 topics ready
Living world
Bodies, plants, animals and the systems that keep them alive.
The human body
5 topics ready
People and society
How people organise themselves, and what happens when they travel, trade and rule.
Government and citizenshipExploration and encounter
2 topics ready
Technology
How tools, machines and computers are designed and used.
Engineering and power
3 topics ready
30 ready to read
Topics ready to explore
Living world · The human body
Anatomy of the human body
What is inside you, and where exactly does it all sit?
5 depths
79 practice questions
Mathematics · Geometry
Angles
How much does a door turn when it opens — and how do we measure a turn?
5 depths
80 practice questions
Living world · The human body
Body systems and how they connect
No organ works alone — so how does a mouthful of roti reach your toes as energy?
5 depths
79 practice questions
Mathematics · Data handling
Data handling
What is a typical value — and how can one number summarise a whole class?
5 depths
80 practice questions
Earth and space · Sun, Moon and sky
Eclipses
If the Moon goes round Earth every month, why isn't there an eclipse every month?
5 depths
68 practice questions
Physics · Electricity and magnetismTechnology · Engineering and power
Electricity
What actually happens between the power station and the switch under your finger?
5 depths
People and society · Exploration and encounter
Exploration: reasons and consequences
What made people sail into oceans they could not map — and who paid for it?
5 depths
75 practice questions
Mathematics · Numbers
Four operations
When should you add, subtract, multiply or divide — and how do you know your answer makes sense?
5 depths
74 practice questions
Physics · Forces and motion
Gravity
Why does everything fall down — and what is the Moon falling towards?
5 depths
70 practice questions
Mathematics · Factors and multiples
HCF and LCM
When will two blinking lights flash together again — and what is the biggest tile that fits a floor exactly?
5 depths
79 practice questions
People and society · Government and citizenship
How government works in India
Who decides what a country does — and where does a citizen fit in?
5 depths
76 practice questions
Physics · Light
Light
What is light, how does it travel, and why can you see this page at all?
5 depths
80 practice questions
Mathematics · Geometry
Lines, rays and line segments
What is the difference between a line, a ray and a segment — and why do railway tracks never meet?
5 depths
80 practice questions
Physics · Electricity and magnetism
Magnets: why do some things stick to a magnet and others do not?
Magnets: why do some things stick to a magnet and others do not?
5 depths
52 practice questions
Mathematics · MeasurementMathematics · Geometry
Measuring and constructing angles
How do you draw an exact 60° angle with only a compass and a ruler?
5 depths
74 practice questions
Mathematics · Patterns
Number and shape patterns
How can you predict the 100th term without drawing 100 pictures?
5 depths
81 practice questions
Mathematics · Numbers
Number system
How do we read, write and compare really big numbers — and why do Indians and the rest of the world put commas in different places?
5 depths
83 practice questions
Mathematics · Numbers
Order of operations
Is 2 + 3 × 4 equal to 20 or 14 — and who decides?
5 depths
75 practice questions
Earth and space · Sun, Moon and sky
Phases of the Moon
Why does the Moon change shape — and why is it never really a different shape at all?
5 depths
75 practice questions
Mathematics · Factors and multiples
Prime and composite numbers
Why are some numbers impossible to split into equal groups?
5 depths
79 practice questions
Mathematics · Numbers
Properties of numbers
Why does 7 × 8 equal 8 × 7, and how can such rules make mental maths easy?
5 depths
85 practice questions
Technology · Engineering and power
Quantum Computing
Quantum Computing
5 depths
59 practice questions
Technology · Engineering and power
Quantum Networks
Quantum Networks
5 depths
61 practice questions
Physics · Light
Quantum Theory
Quantum Theory
5 depths
61 practice questions
Mathematics · Geometry
Shape and space
What makes a square a square, and how many edges does a cube really have?
5 depths
80 practice questions
Physics · Sound
Sound
Why does a drum you cannot touch still reach your ears?
5 depths
76 practice questions
Living world · The human body
The digestive system
The digestive system
5 depths
52 practice questions
Living world · The human body
The Nervous System
The Nervous System
5 depths
59 practice questions
Living world · The human body
The Respiratory System
The Respiratory System
5 depths
52 practice questions
Earth and space · Oceans
Tides
Why does the sea climb up the beach and slide back, twice a day, forever?
5 depths
71 practice questions
How Curiosity works
- ExplorePick a subject, an area, then a question that pulls at you.
- Go deeperEvery topic opens at five depths. Move up and down freely.
- PractiseQuestion banks with hints and a worked solution for every question.
- WishAsk for what isn’t here yet. A person reads every wish.
How content is made
Written by a person, with help — then checked by a person
Every lesson lists its sources and shows whether it has been reviewed. There is no chatbot on this site and no AI runs while you read. If you spot a mistake, please tell us.