Khan Academy Exercises and Videos

Edges, Corners and Faces

2026-05-23T04:10:46.217062

What are faces, edges, and corners? 🎁 Explore 3D shapes like cubes, cuboids, cones, cylinders, and spheres through fun real-life examples. Children learn to count surfaces, edges, and corners step by step.

Alternation of Generations in Plants

2026-05-21T12:20:37.012461

In this video, we look at the process by which plants can switch between or have two types of bodies – the haploid gametophyte and the diploid sporophyte.

Prokaryotic Cell Envelope and it's Modifications

2026-05-21T12:20:37.012461

In this video, we break down the prokaryotic cell envelope—its layered structure and the key modifications that enable protection, transport, movement, and interaction with surroundings.

Division by zero

2026-05-20T12:40:50.119552

In this video, we explore the fundamental concept of division by zero and understand why it is not defined in mathematics. Starting with simple division examples, we gradually move to cases where the divisor becomes zero and see how the logic breaks down. Through clear explanations and visual demonstrations, we show why dividing any number by zero does not give a meaningful result.

Closure property of Whole Numbers

2026-05-20T12:40:50.119552

In this video, we explore the closure property of whole numbers and see how different operations behave within the set of whole numbers. You’ll learn that addition and multiplication are closed operations — meaning the result of adding or multiplying any two whole numbers is always another whole number. But subtraction and division tell a different story: subtracting two whole numbers may not always give a whole number, and dividing them often leads outside the set.Through clear examples and explanations, we highlight which operations keep us inside the set of whole numbers and which ones don’t, helping you build a strong foundation in arithmetic and understand the limits of closure.

How INFOGRAPHICS improve aesthetics - Representing Data

2026-05-18T06:40:44.106025

How INFOGRAPHICS improve aesthetics

Hectares as unit of area

2026-05-18T06:40:44.106025

Hectares as a unit of area

Direct Proportion - Ratios

2026-05-18T06:40:44.106025

Direct proportion

Bar Graphs - Data Handling

2026-05-18T06:40:44.106025

Bar Graphs

Reading bar charts comparing two data sets

2026-05-18T06:40:44.106025

Reading bar charts comparing two sets of data

Divisibility rule for 7 - Divisibility rules

2026-05-18T03:51:26.786642

Divisibility rule for 7

Placenta (How do humans reproduce?)

2026-05-16T16:10:39.739559

Placenta (How do organisms reproduce?)

Co-prime art

2026-05-13T12:50:47.556406

Discover the beautiful connection between maths and patterns through co-prime thread art! Learn how pegs and thread gaps create stunning designs while exploring the concept of co-prime numbers.

Measuring lengths using unit fractions

2026-05-13T12:50:47.556406

Learn how fractions can be used to measure lengths and quantities in everyday life. Explore halves, quarters, eighths, and more through paper folding and visual models.

A Prime Puzzle

2026-05-13T12:50:47.556406

Challenge your brain with exciting prime number puzzles and number patterns! Learn how prime numbers work through fun grids, logic, and problem-solving activities.

Mixed fractions

2026-05-13T12:50:47.556406

Learn how fractions greater than 1 can be written as mixed fractions in a simple way! Understand whole units, improper fractions, and mixed numbers with easy examples and activities.

Equivalent fractions

2026-05-13T12:50:47.556406

Learn all about equivalent fractions through simple, real-life examples like sharing pizza, chocolate, and roti. This video explains how different numbers can represent the same quantity and introduces the concept of a fraction wall to visualize mathematical equality.

Fractional Units

2026-05-13T12:50:47.556406

Understand fractions in the easiest way using rotis, sharing, and real-life examples! Learn about fractional units, comparing fractions, and reading fractions with fun activities.

Irrational number on number line

2026-05-11T12:00:34.889249

This video shows how irrational numbers like √2 and √3 can be located on a number line using a simple geometric method. By using the Pythagoras theorem, the lesson builds step by step to construct these values visually. The explanation makes it easier to understand how irrational numbers fit between whole numbers on the number line. A clear and helpful way for students to strengthen their understanding of real numbers.

Momentum conservation Solved example

2026-05-11T04:40:42.021307

Momentum conservation Solved example

Levers of first, second and third order

2026-05-23T11:07:44.000000

Let's solve some questions on machines and types and uses of simple machines

State building: Roman empire

2026-05-22T16:09:30.000000

Answer questions about the Roman empire based on a passage.

Foraging Societies

2026-05-22T14:58:43.000000

Practice what you learned about how foraging societies used cooperation, tools, and shared knowledge to meet their needs and adapt to their environments.

The South after the Civil War

2026-05-22T14:51:35.000000

In the wake of Reconstruction, what became of the people who lived in the former Confederacy?

Indigenous America

2026-05-22T14:45:44.000000

Test your knowledge of Native American societies and how humans lived on the North American continent.

Understand: Centripetal force

2026-05-22T13:30:55.000000

Check your understanding of centripetal force in this set of free practice questions.

Apply: Orbital motion

2026-05-22T13:28:22.000000

Apply your knowledge of orbital motion in this set of free practice questions.

The Second Amendment

2026-05-22T13:21:18.000000

Explain the extent to which the Supreme Court's interpretation of the Second Amendment reflects a commitment to individual liberty

Changes in ideology

2026-05-22T13:14:17.000000

Test your skills in this quiz on influences on citizens' ideology.

Policy and the branches of government

2026-05-22T13:13:19.000000

Test your knowledge on how the other branches use formal and informal powers to hold the bureaucracy accountable!

Interest groups influencing policymaking

2026-05-22T13:08:28.000000

Test your knowledge on the potential benefits and drawbacks of interest group influence on policymaking.

Ideology and policymaking

2026-05-22T12:59:28.000000

Test your knowledge on how US political culture influences policymaking over time!

Social movements and equal protection

2026-05-22T12:56:47.000000

Test your skills in this quiz on social movements and equal protection.

Postwar diplomacy

2026-05-22T12:38:31.000000

Test your knowledge on the consequences of American involvement in World War II!

Market Revolution: industrialization

2026-05-22T12:36:06.000000

Test your skills on the causes and effects on the innovations in technology, agriculture, and commerce over time.

A changing economy

2026-05-22T12:35:19.000000

Test your skills on the economic and technological changes of period 9!

Immigration and migration in the Gilded Age

2026-05-22T12:34:32.000000

Practice your skills in this exercise on immigration and migration in the Gilded Age.

Culture from 1945 to 1960

2026-05-22T12:33:53.000000

Test your skills on the development and the responses to mass culture!

The Great Society

2026-05-22T12:30:10.000000

Practice your skills in this quiz on the Great Society.

The rise of political parties and the era of Jefferson

2026-05-22T12:25:28.000000

Test your skills on the causes and effect of policy debates in the early republic.