More than 2,000 years ago, a Greek scientist named Archimedes jumped out of his bath shouting “Eureka!” because he had just made a brilliant discovery about how things float and sink. His idea still explains why giant ships can stay afloat while tiny pebbles sink to the bottom.

In this activity, you will explore this very discovery for yourself. When you lower different objects into water, you will discover that the water pushes upward, almost as if it’s trying to lift them. You will see how this buoyant force depends on how much water is displaced – and by the end, you will understand the science behind floating boats, diving submarines, and even your favorite bath toys.

"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world," declared the ancient Greek scientist Archimedes. He wasn’t exaggerating – he was revealing one of the most powerful ideas in science. Long before modern machines were invented, people used levers to lift stones, move logs, and build temples and pyramids. A lever is a simple tool, but it can do remarkable things – it lets you use a small force to move a large weight, just by changing how and where you apply that force.

In this activity, you will explore how levers work and discover for yourself how changing the position of the fulcrum, load, and effort can make lifting easier – just as Archimedes described thousands of years ago.

A pendulum swings with a graceful rhythm that seems almost magical – steady, smooth, and predictable. From the ticking of old grandfather clocks to the motion of playground swings, pendulums have fascinated scientists and inventors for centuries. They’ve been used to measure time, study motion, and even understand gravity.

In this activity, you will investigate what factors affect the speed of a pendulum’s swing. Does a heavier bob make it move faster? Or does the length of the string play a more important role? By observing, experimenting, and drawing conclusions, you will discover the key factor that determines the pendulum’s steady beat.

Your voice is like a fingerprint made of sound. No one else has the exact mix of tones that you produce. Long before smartphones existed, radio operators could recognise who was speaking just by listening carefully. Today, speech-recognition apps do something similar using maths. They look at patterns hidden inside your voice to figure out what you are saying.

In this activity, you will explore what makes your voice unique by studying the frequencies that appear when you speak different vowels.

Every voice has its own unique sound, just like Amitabh Bachchan’s deep and powerful voice or Taylor Swift’s soft and high one. Just like musical instruments, our voices can produce a range of notes or pitches. In Indian music, these notes are known as Sa, Re, Ga, Ma, Pa, Dha, Ni, Sa′. Great singers like Lata Mangeshkar and Kishore Kumar are known for their wide pitch range, as they could comfortably sing from a low Sa to a much higher Sa′.

In this activity, you’ll explore how pitch changes as you move from Sa to Sa′ and see how the range of frequencies varies between different people. You’ll get to see your voice as sound waves on your phone using a frequency analyzer app like Spectroid.

You have learnt that dark-colored clothes or surfaces heat up faster in the sun. That’s because dark colors absorb most of the sunlight that falls on them. That is why it is recommended that one should wear light color clothes in summer. But have you ever thought about the other colors – red, blue, green, or yellow? Do they all absorb heat the same way, or are some better at trapping sunlight than others?

Sir Isaac Newton discovered that sunlight could be split into a rainbow of colors – violet, indigo, blue, green, yellow, orange, and red. In this activity, you will explore how each of these colors absorbs heat differently and find out which one traps the most energy from sunlight.