Egg Into Bottle

Find a glass bottle that has a mouth slightly smaller in diameter than an egg. Pour some hot water into the bottle (be careful!), shake it vigorously and empty the water.

Peel a soft-boiled egg and place it on the mouth of the bottle. Leave it there for a while and it will get sucked inside.

The vapor from the hot water drives the air out of the bottle. Once the egg seals the top of the bottle, the air can’t get back in. As the water vapor cools, it turns back into water, causing the pressure inside the bottle to drop. The higher pressure of the outside air pushes the egg into the bottle.

Floating Arm

Stand next to a wall with one arm pressing against the wall. Push your arm against the wall as if you're trying to move the wall. Don't push with your body, only push with your arm. Count to 20 as you push your arm against the wall.
Now step away from the wall and let your arms hang relaxed at your sides. Your arm will "magically" start to rise into the air by itself!

Soap Rainbows

Here's how to make soap rainbows with your hands! First get your hands good and soapy over the sink. Then place your palms together. Pull your hands slowly apart. Make sure that your thumbs and index fingers don't lose contact with each other. Check out the cool swirling colors!

Bubbles with Your Hands

Here's how to make huge soap bubbles with your hands! First get your hands good and soapy over the sink. Then make an "OK" sign with your fingers, but curl your index finger all the way in towards your hand.
Now slide your index finger out towards the tip of your thumb. Make sure that your index finger stays in contact with your thumb! Now you should have a film of soap between your index finger and thumb.
Take a deep breath, then blow into the film of soap to make a bubble. It might take practice to get it to work! We have found that it helps if you have plenty of water on your hand, and hold your hand close to your mouth.

Toothpick Torpedo

Dab a little shampoo on the blunt end of a wooden toothpick.

Drop the toothpick in a pan of water. The toothpick will start moving in the direction of the sharp end.

Shampoo contains agents that reduce the surface tension of liquids. As the shampoo on the end of the toothpick dissolves, it reduces the water’s surface tension around it, thus releasing the water’s hold on that end of the toothpick. The water around the other end of the toothpick still has surface tension, so it pulls the toothpick in that direction.

Reading Through an Envelope

With a black felt-tip pen, write a three-letter word in large letters on a white piece of paper. Place the paper in a brown envelope, and insert that envelope into a white envelope. The writing on the paper should now be impossible to read.

Get a piece of dark construction paper or tear out a page from a magazine that is printed on both sides. Roll up the paper into a four-inch-long tube. When you hold the tube against the envelope, you’ll be able to read the writing inside.

Usually you can’t read the writing inside an envelope because of the light reflected off the envelope’s white surface. But the tube blocks that reflected light, so you see only the light coming through the envelope.

Bending Light Through Water

Punch a hole in a clear plastic bottle two inches from the bottom. Put your finger over the hole, fill the bottle with water and cap it to keep it from draining out.

Darken the room and cover part of a flashlight with your fingers to make the beam narrower. When you take the cap off the bottle, the water will flow out in an arc. Shine the flashlight at the stream from the side of the bottle opposite the hole. The light will bend with the arc and create a bright glow where the water hits the sink.

When the light in the stream strikes the boundary between the water and air, much of the light is reflected back into the stream. The light continues this internal reflection all along the arc formed by the falling water. The same principle is used to transmit light signals through flexible optical fibers.

A Flying Trash Bag

Hold the mouth of a black trash bag in one hand. Use a hair dryer to blow hot air into the bag.

Seal the mouth of the bag with tape. Tie a long piece of string around the tape so you can hold it. Take the bag out into the sun. The bag will rise slowly into the air. (It’s best to do this trick in an open area on a windless day.)

How Does It Work?

Since the bag is black, it absorbs heat from the sun. That heat makes the air inside the bag expand and become lighter. When the bag and the air inside are lighter than the surrounding air, the bag starts to rise.

A Candle That Sucks Water

Place a candle upright in the middle of a saucer. Fill the saucer with water. Light the candle. Place a glass over the candle. When the flame goes out, the water in the saucer will get sucked into the glass.

How Does It Work?

When the candle is burning inside the glass, the heat makes the air expand, so some of the air escapes outside the glass. The candle goes out after it uses up all the oxygen, so the air inside the glass cools. As it cools, the pressure inside the glass drops. Some of the carbon dioxide formed by the flame dissolves in the water as well, decreasing the pressure even more. The water outside the glass on the saucer is forced into the glass by the higher aire pressure outside.