To make the instant fan, you will need:

• A pencil with an eraser at the top

• A knife or cutter

• A thumb pin

• An empty refill of a ballpoint pen

• A piece of chart paper (5cmx1.5cm)

Method

1. Using a knife, cut five or six notches into a pencil at regular distances from each other.

2. Fix the piece of chart paper on the eraser at the end of the pencil with a pin.

3. Now drag an empty refill along the pencil notches repeatedly.

What do you notice?

The flap of paper at the end of the pencil starts to rotate like a fan!

How does this happen?

The exact mechanism that makes the paper flutter is pretty complex, and several researchers have tried to figure it out. Quite simply put, the fan rotates because of vibrations caused in the pencil.

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by Arvind Gupta
(www.arvindguptatoys.com)

Artwork by Adarsh Achari

You will need

Method

1. Stick two bottle caps back-to-back, using insulation tape.

   

2. Use scissors to make two holes next to each other in the bottle caps. Now, using a needle, make small holes on one end of each straw.
   

3. Insert the perforated ends of the straws, into the two holes you just made in the bottle caps. Make sure the straws go through to the other end.
   

4. Attach an empty bottle to one side of the cap-and-straw structure. Fill another bottle with coloured water, and attach it to the other end, such that the empty bottle is upside-down.
   

5. Once all the caps are shut tight, invert the structure so that the bottle with the coloured water is on top.
   

   You will notice that bubbles emerge from the straws at both ends. Invert the structure again after a while to keep the experiment going.

How does it work?

The coloured water in the bottle on top starts to travel through the straw to the empty bottle below it. Air bubbles enter the same straw through the tiny holes, and these bubbles are expelled along with the coloured water into the bottle below. As the empty bottle fills up, the air is pushed upwards through the straw. When this air rushes up, some of the water from the bottle above enters through the holes in the second straw and spouts out of the other end like a fountain!

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by Arvind Gupta

The strange ways in which Styrofoam behaves under pressure.

Years ago, when I was in college, I went out to sea on a sailing ship called the Westward. I was very seasick and spent most of my time throwing up overboard. Soon, I wisened up and figured that I had to throw up on the leeward side of the ship (where things get blown away from you) and not on the windward side (where everything hits you in the face!).

You will need:

• Filter paper
• A glass
• Sketch pens or whiteboard markers

Gardening requires patience, a love for the natural world and a keen sense of observation. It isn’t entirely a walk in the park, but it is hugely rewarding and a fun activity to introduce into your everyday life.

You will require

• Soil
• Containers
• Hose pipe
• Digging equipment
• Tomato seeds, petunia cuttings from the local nursery and sprouted garlic bulbs from your kitchen

In which a professional chef reveals the tricks of flambéing and caramelisation. Psst, readers, you can try this at home!

The 1950s are best remembered for the emergence of rock-nroll and the beginning of the Space Race when the Soviet Union launched Sputnik I. For us culinary geeks, a.k.a chefs, it also marks the decade that saw the birth of a popular dessert.

The process of convection occurs naturally around us. It is responsible for the distribution of heat in the Earth’s atmosphere as well as for sea breezes and thunderstorms. The principle on convection has also been used to run heating and cooking devices.
Make a solar pinwheel and see it in action!

A fifth grade student performed this experiment at an NCL outreach programme in a Pune school:

Common synthetic glues typically contain long, string-like molecules that dissolve in water. These molecules are polymers. When you add borax to the glue, the polymers crosslink. This means that they form chemical bonds so that the string-like molecules get knotted. If many such knots are made, interesting things happen. Like slime!

You will need:

• An old 500ml plastic bottle (small bottles work best)
• Scissors
• Marker
• Paint (glass, enamel, acrylic, enamel or a spray can)

You will need:

• Bottle:  Start with the biggest one you can find. A widemouthed Bournvita/Horlicks bottle is great for beginners.
• Small plants: They shouldn’t outgrow the bottle!
• For the plants to grow you will need: Soil, moss, small pebbles (small enough to fit in your bottle’s neck) and some charcoal.
• Tools: A coat hanger or thick wire cut into short strips, so you can reach inside the bottle.