Sunday, December 14, 2008

Stalactites hold tight!

I was looking at the icicles on my friend Gerry's porch Torch Lake Views when I thought that this would make a great science experiment.

So here's how to make stalactites and stalagmites.

Collect two glass jars, two fishing sinkers, epsom salts, string and a small plate. Fill the glass jars with hot water from the tap and stir in as much epsom salts as will dissolve. Wet a piece of 18 inch long string, tie a sinker to either end and hang it in the solution as shown in the diagram. Leave it undisturbed in a warm place for a week, then come back daily and check it out.

Here's a handy saying to help you remember which is which:

Stalactites have to hold on tight to stay on the ceiling of the cave. Stalagmites have to be mighty to stand up on the floor of the cave.

* You can also try this with baking soda, salt or sugar. And hey - add some food coloring just for fun!

Try looking at your crystals through a magnifying glass. What shape can you see?

Word Bank
week, salt, soda, cave, warm, add, epsom salts, magnifying, crystals, diagram, ceiling

Friday, December 12, 2008

Lost in Space

Do you ever feel like you want to get lost in space? Well now you can when you make your own balloon rocket.

The scientific principles involved are the uses of pressure to cause movement. In other words, you are learning how to make a rocket fly.


- a balloon
- a paper bag
- string
- a straw
- sticky tape
- a tape measure


Decorate your paper bag so that it looks like a rocket. Attach the paper bag to a straw. Put the straw through the string that is stretched tight across the room. Put the balloon in the bag and blow it up.

Ready? Let it go!

What is Happening?

This balloon rocket experiment uses the pressure difference between the gas inside the balloon to that outside the balloon. The gas inside moves towards the area of lower pressure. The gas pressures are moving towards an equal state; technically this is called moving toward equilibrium.
This experiment is a good demonstration of the ability of pressurized air to make an object move.

Thursday, December 11, 2008

Can you get an Egg into a Bottle?

Is it really possible to get an egg into a bottle? It is, and here is how you do it.

Drop three lit matches into a glass bottle that has a narrow neck (a 600 mL bottle works well.)

Quickly put a peeled, hard-boiled egg on the mouth of the bottle.
The egg should squeeze its way through the mouth of the bottle and get inside it.

What happens you may ask? The lit matches heat the air inside the bottle. When air is heated it expands and takes up more room. As the heated air expands, some of it escapes out the bottle. When the matches go out, the air inside the bottle cools and contracts (and takes up less room), and this makes the pressure inside the bottle less than the pressure outside. The greater pressure outside the bottle sucks the egg into the bottle.

Thursday, December 4, 2008

STOP PRESS! It's snowing in Canberra!

Wrap up tight in that pashmina, Ms S. It's snowing on the Science website in cool Canberra.

Can you make your own snow? Here's a fun link if you want to give it a try.

Wednesday, December 3, 2008

Seahorses have a secret...

And the secret is that the male carries the eggs.

Seahorses live in small compacted places. They like to eat shrimp and lots of other small kinds of fish. The eggs are in the male's pouch for nine days then they hatch. Some Seahorses hatch 2,000 to 3,000 eggs.

There are 32 different species of seahorses. They live from three to five years in the wild.

The Latin name for a seahorse is Hippocampus. You can also read more about seahorses here. The one in the picture lived a very long and happy life.

Tuesday, December 2, 2008

Somewhere over the rainbow

What you need to make a jello rainbow:

Measuring jug
Boiling water 125 mls
Cold water 125 mls
Packets of different colored jello


1. Empty jelly crystals into a measuring jug.
2. Add half a cup of boiling water. Get an adult to do this.
3. When it is stirred together, add a half cup of cold water.
4. Stir until the jelly crystals are completely dissolved.
5. Pour into a container and refrigerate until it is almost set.
6. Do steps one to five several times using different colors of jello.
7. Use a glass container to layer the many colors of jello to make a rainbow effect. Refrigerate until it is set hard.


Did you ever drink unset jello? Try it, you might like it!
Did you ever try to make a jello sculpture?


- In 1845, industrialist Peter Cooper (who built the first American steam-powered locomotive, the Tom Thumb), obtained a patent for making powdered gelatin.
- Some discontinued flavors are: Italian salad, pickle and bubble gum.

The lyrics for the Aeroplane Jelly Song:

I like Aeroplane Jelly, Aeroplane Jelly for me.
I like it for dinner, I like it for tea,
A little each day is a good recipe!
The quality's high, as the name will imply,
It's made from pure fruit - one more good reason why
I like Aeroplane Jelly, Aeroplane Jelly for me!

Supersize me!

The kitchen is the best place to do science experiments! Today, we are going to make pancakes!
Did you know, baked goods are like balloons and need gas to rise? Rising agents like baking powder and baking soda produce carbon dioxide, and trapped air and steam are additional sources of gas. The protein in eggs and flour provide a stretchy structure that traps the gas as it expands due to heat, causing the batter to rise.

If you like pancakes and want to make some then follow these instructions.

1 cup self-raising flour
1 cup milk
1 egg

1. Pre-heat a large non-stick frying pan.
2. Add all ingredients into a bowl and mix until combined.
3. Lightly grease the pan with butter or cooking spray.
4. Cook large spoonfuls of batter until bubbles burst on top and the edges start to go dry.
5. Turn and cook other side until golden.

Delicious toppings:
Maple syrup, lemon juice and sugar, jam.

Monday, December 1, 2008

Stun your friends with a playdough sculpture


half a cup of salt
1 cup of plain flour
2 tablespoons cream of tartar
1 cup of water
1 tablespoon of oil
food colouring

What to do:

  1. Mix all the ingredients together in a bowl.

  2. Knead it until the dough is pliable.

  3. Store it in a well sealed plastic bag or a container.

Things you can make and even bake:

An ashtray, Christmas ornaments, a pendant for a necklace, animals, or a sculpture.


Salt is used as a preservative.

Salt is the most common food seasoning.

Over consumption of salt can lead to high blood pressure.

Salt is bad for plants and can kill them.

Bread Making Word Bank

bread, yeast, breadmaker, flour, water, loaf, crust, ingredients, dough, knead

Bread Making

What You Need


Here is a link to make bread at your home. Breadmaking

Monday, November 17, 2008

How to Make A Solar Oven

Equipment and Material

• 1 pizza box
• newspapers
• scissors
• tape
• black construction paper
• clear plastic wrap
• aluminum foil
• ruler


1. Draw an 8 1/2 inch x 11 inch square in the
lid of the assembled box.
2. Cut out three sides of the square, and fold
the flap back along the uncut edge.
3. Cover the inside of this flap with aluminum
foil, using tape to hold the edges securely.
4. Line the inside bottom of the box with black
construction paper. Use tape to hold the edges down.
5. Create insulation by rolling up some newspaper (about 1 1/2
inch thick) and fitting it around the inside edges of the box.
6. Tape one piece of plastic wrap (stretched tightly) to the underside
of the lid opening, to cover. Tape another piece on the top of the lid opening, to create a layer of
insulation that will help hold the heat in the box.
7. Prop the box at an angle facing the sun. Use a ruler to prop the flap open.

On a hot, sunny day the temperature can reach 200°°F in
your oven! Use it to make smores, or to warm some muffins.

Thursday, November 13, 2008

Who are you calling a Pee Wee? - the Magpie Lark

Hello to my commenter. :)

How about a couple of blown up balloons tied to the chairs or table top? Streamers - like you use for a party - we scared away crows at school outside our classroom this way. The paper streamers flutter in the breeze and are off putting to birds. A mobile hanging up above the table? One that will chime or make a musical sound? This may disturb them. Good luck!

The adult male has a white eyebrow and a black face whereas the female has a white face and doesn't have a eyebrow. The young, no matter what gender, have a black forehead, a white eyebrow and a white throat.

Pee wees can be found in Australia, New Guinea and Timor. They can be found in almost any habitat except rain forests and the driest deserts. Birds that don't breed and young birds make large wandering groups that move flock together. These groups can sometimes consist of several thousands of birds.

The pee wee is a mostly ground dwelling bird and can be seen slowly searching the ground for a variety of insects and their larvae. They also like to eat worms and freshwater invertebrates.

This bird does not at all sound like the noisy magpies but yet, does not sound as sweet as the lark but... as Slinky likes to say - "I like to think that they are there, having a peaceful time as they fly, eat and enjoy life."

Here is a female on her nest in Brisbane in an African Tulip tree about 3 metres off the ground. The nest is covered with mud on the outside and the eggs have not hatched out yet. They lay from three to five, and they are pale brown with splotches.

* Can you name six black and white birds found in Australia?

* Did you know? Magpie larks are very attracted to mirrors and will look at themselves for hours.

(Article written by Slinky.)

Friday, November 7, 2008

Why is it so?

This is a simple (excuse me, I am laughing really hard here) test to see if you are correctly processing what you are reading. After all, if you don't read your Science instructions correctly you will end up with very queer results in your experiments.

Take this color test and see how you measure up.

Sunday, November 2, 2008

Are these colors for real?

... or are they photoshopped? Wait for it - they are REAL!

Nature gives us some pretty amazing sights, and on Mommy Bytes by Angela we find an unusually colored frog.

Can you find some more blue creatures in nature? Here are some other examples:

This is a blue footed bird from the Galopagos Islands.

And on Fish and Frog, Turtle and Blog, we can learn all about the beautiful blue damselfly.

Tuesday, October 14, 2008

Test Tube Aliens - Are they real?

They LOOK real! After looking up Roswell on Google, we studied two views of an alleged alien crash site.

We discovered that the town of Roswell, New Mexico, USA, became famous on July 7, 1947, as there was speculation that an alien space ship had crashed near there.

Reports from the United States military say that what was actually recovered was debris from a high-altitude surveillance balloon.

However, many UFO believers spoke up to the media, saying that a crashed alien space ship and some UFO bodies were recovered from the crash site and that the military covered it up.

The name Roswell is now mentioned whenever talk turns to UFOs. It's the most famous UFO incident. It even got its own TV series!

So to simulate the Roswell incident, and just in case it wasn't a weather balloon, or a sleek Stealth bomber, we hatched and raised a Test Tube Alien.

They come dehydrydrated, and encased in a white cocoon which melts away as the alien hatches, until a very live looking alien is revealed. To hatch it, you add water and keep adding water until it stops fizzing. Then you feed it. The heart beat is fascinating to watch as it flashes from green to orange to red - signifying that the alien is alive and well!

Word Bank:

alien, test tube, live, water, melt, cocoon, heart, hatch, fizzing, encased, revealed, dehydrated.

Monday, October 13, 2008

Cyber Scope! Turn your world upside down!

Can you imagine how strange the world would look if everything was upside down? When you put on the Cyber Scopes glasses, that is exactly what happens! Students will have a fun time watching each other try to complete challenges while wearing the disorienting glasses.

It's a board game with a difference. It contains a pair of special glasses, game board, 16 puzzle pieces, 7 puzzle cards, 1 foam ball, dice, a pen and two timers. Students compete to make their way around the game board as quickly as possible by completing tasks wearing the Cyber Scopes. The tasks range from putting together a puzzle, to catching a ball in the air, to reading a single word.

While the tasks may initially sound easy, they become a whole lot more difficult when the world is turned upside down by the Cyber Scopes glasses! These distinct glasses put a new spin on the board game that will have you attempting to work in reverse, upside down, in a disorientated state - all in the safety of your classroom. Is it all an illusion, or is it real? You decide!

Wednesday, August 27, 2008

It's moving!

It's moving! Hold the page still! Double click on the image to make it larger.

An optical illusion is also called a visual illusion. The brain processes the information given to it by the eye, but - the effects of certain stimulation, like brightness, tilt, colour or movement, can give a false perception.

Ms S once watched a movie called "The Goonies" and she believes that if you feed these things Dr Pepper, they will multiply!

Wednesday, July 9, 2008

The Monarch Butterfly

To start with, here is a website I follow which gave me the idea.

Torch Lake Views

Here is a fun website to look at, with migration maps and information inside.

Monarch Butterfly site.

Now we have the activities:

1. Show the life cycle of the Monarch Butterfly in a diagram.
2. On a map, show where it lives and how it travels.
3. Full illustration, either by drawing or scrapping.
4. Interesting and unusual facts.
5. And just for fun, write a Haiku poem (5, 7, 5) about the Monarch Butterfly.

Tuesday, June 24, 2008

Do oil and water mix?

What happens when an oil tanker spills oil into the ocean?

The oil floats on top of the water, causing environmental damage and killing fish and seabirds. Oil floats on water because it's less dense.

Oil and water don’t mix.

What you need:

four clear glasses, each half full of water
cooking oil
food colouring – red or blue show up best
liquid detergent

What to do:

Add a few drops of food colour to the first glass and stir. Notice how well the colour mixes with the water.
Pour some cooking oil into the second glass. Does it mix in like the food colour did? Try stirring the oil and observe what happens. The oil will eventually rise to form a layer on top of the water.
Pour enough cooking oil into the third glass to form a layer on top of the water approximately five centimetres thick. When the oil layer has settled, add a few drops of food colour. Don’t stir. Watch how each drop behaves as it hits the oil layer.
Now mix everything in together. What happens to the drops of colour? Some tiny drops of colour will probably stay in the oil layer. Watch what happens to them after a while.
Create the same oil and water mixture in the fourth glass, with several drops of food colour. Add a teaspoon of dishwashing detergent and stir vigorously. What is different this time? Notice the colour of the oil layer. Is it the same as the water layer?

What's happening:

Even when you stir them together, they will soon separate. The oil, which is lighter (or less dense), rises to the top. Food colouring is water-based, so it mixes easily with water, but can’t mix with the oil. Did you notice how the drops of food colour behaved when they travelled through the oil? Sometimes the food colour forms perfect little beads, which slowly drop through the oil layer.

Slime - make mine lime

You can make your own cornflour slime to learn about fluids and viscosity.

To do this experiment you will need:

food colouring
a small mixing bowl

What to do:

Pour some cornflour into a mixing bowl.
Stir in small amounts of water until the cornflour has become a very thick paste.
To make the slime the colour of your choice, thoroughly stir about five drops of food colouring into the mixture.
Stir your slime REALLY slowly. This shouldn't be hard to do.
Stir your slime REALLY fast. This should be almost impossible.
Now punch your slime REALLY hard and fast. It should feel like you're punching a solid.
What's happening:

Anything that flows is called a fluid. This means that both gases and liquids are fluids.
Fluids like water which flow easily are said to have low viscosity, whereas fluids like cold honey which do not flow so easily are said to have a high viscosity.
Cornflour slime is a special type of fluid that doesn't follow the usual rules of fluid behaviour. When a pressure is applied to slime, its viscosity increases and the cornflour slime becomes thicker.
At a certain point, slime actually seems to lose its flow and behave like a solid. Cornflour slime is an example of a sheer-thickening fluid.

Make two columns in a book and call one "Low Viscosity" and the other "High Viscosity". Which column do these liquids go into:

honey, molasses, water, Dr Pepper, whipped cream, jam, ketchup, milk, yoghurt, juice, tea.

Invisible Ink - can you see it?

Some inks are developed by heat.

Some of these oxidize when heated, and usually turn brown. For this type of 'heat fixed' ink, any acidic type of fluid will work. As a rule of thumb, the most secure way to use any particular ink is by diluting it - usually with water - near to the point when it begins to get difficult to develop.

Cola drink (diluted)
Honey (diluted)

Lemon, apple or orange juice
Onion juice
Soap water
Sugar solution

Ah ha! I am about to use invisible ink to write you a message:

Did you read it? First one to tell me the correct answer wins a prize!

Keep a Pet Journal

You might like to work in pairs or teams.

How are you going to format this? Will you blog it? Will it be in poster form? Use a class work book? If so, which one?

Is your pet real or just on your wish list?

Keep it up every day for a week from Monday through to Friday, then we can spend a week finalising the presentation, then we can do a class sharing session.

Your assessment will be based on your teamwork and cooperation, your illustrations, your oral presentation at the end, and the quality of your writing.

Read Pyewacket's journal from topcatrules before you begin.

Monday, May 12, 2008

Sultana Soda Pop

The Invisible Shield

Hot on Top

Thursday, May 1, 2008

I'm going to make you a star!

Expanding Toothpicks


· 5 toothpicks
· eyedropper
· small plate
· water

Time required:

5 Minutes

What to do:

Snap all 5 toothpicks so they are bent, but not completely in two parts - they need to be still connected.
Arrange the bent toothpicks in the centre without letting the ends touch.
Using the eyedropper add 5 drops of water to the centre of the toothpicks. Make sure the drops of water touch the bent corners of all toothpicks.

Watch the toothpicks. If necessary add a couple more drops of water.

What’s Happening?

The broken wood of the toothpicks absorbs the water they are sitting in. As the water is drawn into the toothpick (by capillary action) the wood expands. The expanding wood on the inside of the break pushes against itself which makes the toothpick straighten out. As the toothpicks push out they form the star shape.

Wednesday, April 2, 2008

Dancing Popcorn


• water
• plastic cup
• popcorn
• 1 teaspoon
• 1 tablespoon
• Sodium Bicarbonate
• vinegar

What to do:

1. Fill the plastic cup with water until it is ¾ full.
2. Measure half a teaspoon of sodium bicarbonate.
3. Add the Sodium Bicarbonate to the water and stir until it has dissolved.
4. Add 4 kernels of popcorn to the cup.
5. Add 1 tablespoon of vinegar to the cup.
6. Watch closely for at least 2 minutes.

I predict that the kernels will sink but bubbles will be created because of the vinegar and the sodium bicarbonate. The bubbles attach themselves to the kernels and they will float up. Then the bubbles pop and the kernels sink, then they rise, then they sink.

What actually happened was the kernels sank at first but the bubbles were created because of the vinegar and the sodium bicarbonate, then the kernels went up and down.

Tuesday, April 1, 2008

Rocket Science

Rocket Tea Bags


1 tea bag


Adult Supervision

Let’s do it:

1. Remove the string and tag from the tea bag.

2. Undo and remove the staple and then empty out the leaves.

3. Make the tea bag material into more of a tube by putting your finger into it. Careful not to tear the material!

4. Stand the tube vertically on a flat dry surface, open end facing upwards.

5. Ignite the rocket by lighting the top end of the tea bag tube and stand back!

I predict that the tea bag will rise up because the air inside the tea bag is warm because of the fire and the air on the outside is cold. The warm air rises and lifts the tea bag like a hot air balloon.

What happened was we launched two rockets and the tea bags rose up because the air inside the tea bags was warm because of the fire and the air on the outside is cold. The warm air rises and lifts the tea bag like a hot air balloon.

Thursday, March 27, 2008

Go with the flow

What do I need?

A clear plastic bottle
Liquid hand soap that has glycol stearate in it
Food coloring
Clear tape

Fill the bottle or jar about 1/4 full with liquid soap. Add a drop or two of food coloring. The coloring will make the swirls easier to see.

Turn on your tap so you have just a trickle of water. Fill the bottle all the way to the very top.

Screw the cap on the bottle. Turn the bottle upside-down a few times to mix the soap and water. If you get foam, take the cap off and trickle some more water into the bottle. The foam will run over the edge. Recap the bottle tightly.

Dry the bottle and the cap, then wrap clear tape around it so the bottle won't leak.

- Twirl the bottle slowly. What do you see? What happens when you stop twirling the bottle? What happens if you spin it quickly?

- Try shaking the bottle up and down or side to side. What different patterns do you see inside the bottle?

If the liquid inside the bottle looks like it's all one solid color, just twirl or shake it again to make more patterns. If the cap on the bottle is sealed, Go with the Flow can last for years.

- Why can I see patterns in the water?

Normally, you can't see how the water is moving inside a full jar of water. Water that's moving in one direction looks the same as water that's moving in another direction. But glycol stearate, the chemical that gives some liquid hand soaps a pearly look, lets you see patterns flow in water.

- What kinds of patterns can I see in my jar?Who cares about these patterns?

When you turn the bottle slowly, you'll probably see smooth streaks in the water. When layers of water are moving slowly and smoothly past each other, you get this pattern, which scientists call laminar flow.

When you suddenly stop turning the bottle, or when you turn it very fast, you may see lots of swirls and wavy patterns. When one layer of water moves rapidly past another layer of water, it causes turbulence, which you see as swirly patterns.

When people design airplanes, cars, boats, golf balls, and other things that move through air or water, they study the patterns blowing air or flowing water makes as the object moves through it. Differences in the flow of air or water can affect how well an airplane flies, how much mileage a car gets per gallon, how fast a boat can go, or how far a golf ball will fly when you smack it with a club.

Wednesday, March 26, 2008

How to Dye Celery

Things you’ll need:

A glass, big enough to hold celery stalks and leaves upright
Food coloring
Fresh celery stalks
Cutting board

1. Fill a glass of water about half full of water and then add some food coloring to the water. Dark or bright colors show up best.

2. Check the celery every hour. After about an hour, it will start to show some of the food coloring going up the stalk. You can measure how far the color goes up the stalk every hour. In time, most of the celery will be colored.

3. Water is absorbed by a plant. It travels up the stalk and then goes into the leaves. This is an explanation of how water is circulated in plants. You will need to leave some leaves on your celery stalk, as a plant's circulation works by "transpirational pull" — that is, the leaves are breathing.

Word Bank:

water, celery, dye, plant, mix, spoon, stalk, circulation, leaves, breathe, measure, experiment.

Tuesday, March 25, 2008

Paper planes

Build a special paper airplane to demonstrate how and why airplanes and most birds can fly (when they're not flapping their wings). Cut out the airplane's shape along the dark solid line. Next, fold the top half at the dotted line so that it meets the bottom half. Don't, however, fully crease the paper at the fold (we want to make a nice 'tear drop' air foil shape).

After folding the paper back, put a small piece of tape at the wing tips and at the center at the points marked A, B, and C. Now fold the plane along the center crease so that it creates a flattened out 'V'. The angle of the 'V' should be no more than about 15 degrees. Test fly the plane and adjust its stability.

Keep the nose of the plane from rising (stalling) by adding a small weight to the nose (point D), a paper clip or two does nicely. You can also adjust how much the plane dives or climbs by cutting small slots in the tail of the plane and bending the paper at the cuts up or down. Experiment with putting them up or down and seeing what effect that has on the way the plane flies.

What's going on?

Contrary to popular belief, airplanes don't float on the air, they're sucked up into it. This reason is known as Bernoulli's Principle. It says: " air travels faster [than surrounding air] across a surface, the air pressure against it is reduced...". By curving the top of an airplane's wing, air above it has to travel farther (as the distance is greater) than the air below, forcing the air to move faster.

The result is lower pressure on top and more pressure on the bottom. Another name for this is lift. The higher pressure below the wing is just like someone pushing from below the wing; the lower pressure above the wing is like someone pulling it up (like sucking on a straw to draw up milk in a glass).

If a wing has enough lift upwards, it moves upward, if a wing has lift downwards, it moves downward. The plane that we built, the "Bernoulli Plane" has a real airfoil and more closely resembles and flies the way that real planes and most birds do.

Monday, March 24, 2008

Static Electricity

Static electricity occurs, for example, when you rub a balloon on your shirt. The friction between the cloth and the balloon causes electrons to transfer from your shirt to the balloon. The shirt then has an overall positive charge because it has more protons than electrons. The balloon takes on a negative charge because it has extra electrons. The balloon will then stick to the shirt or to another surface, such as a wall.

Static electricity has many uses in homes, businesses, and industries. For example, the copying machines found in most offices are electrostatic copiers. They make duplicates of printed or written material by attracting negatively charged particles of toner (powdered ink) to positively charged paper. Static electricity is also used in air cleaners called electrostatic precipitators. These devices put a positive electric charge on particles of dust, smoke, bacteria, or pollen in the air. Negatively charged collector plates attract the positive particles out of the air.

Wednesday, March 19, 2008

A bright idea!

Charge up a light bulb

Ever had this happen in your house - something gets broken and Dad goes over and takes a look at it. He studies it for a while and then suddenly - bing.... a little light bulb goes on above his head? Everybody in the house sighs and knows it's in everyone's best interest to get out of there - quick.

In this experiment, we'll make a fluorescent light bulb 'go on' - literally. And no evacuation will be called for...

Take the comb and light bulb into a dark closet.
Take the comb and rub it thoroughly through your hair. If you don't have any hair, a wool shirt or sweater will work fine.
Now hold the comb to the metal end of the light bulb while carefully watching the filament in the bulb.

Pretty cool, huh? When you rub the comb through your hair, the friction between your hair and the comb actually causes electrons (a negatively charged subatomic particle. Electrons are found at varying distances from a atom's nucleus. They make up almost the entire volume of a atom but only account for a small part of the atom's mass.) to travel from your hair to the comb.

Your body (hair) becomes positively charged (because it has more protons than electrons) while the comb becomes negatively charged (it gained electrons from your hair) . The comb, in effect, becomes charged. When you touch the comb to the end of the light bulb, the charged comb discharges into the light bulb causing the bulb to emit small pulses of light.

Monday, March 3, 2008

The Breathing Egg

Do eggs really breathe? Here's your chance to find out! In this egg-speriment, you'll discover the real truth about whether eggs actually breathe or not.
Question: Do eggs breathe?


1 egg
small clear jar (clean jars work) or glass
hot water
magnifying glass
adult helper


1. Put the egg in the jar (without cracking it!) and fill the jar with hot tap water
(as hot as you can get it).
2. Set the jar on a table and watch it for several minutes.
3. If you see anything changing, examine it closely with the magnifying glass.

What Happened - and Why?

Tiny bubbles will start to appear on the egg shell. The bubbles will break free and float upward through the water. That's because the egg shell has tiny openings (so tiny, they are invisible to the naked eye) called pores. Each egg has about 7,000 pores. Inside the shell there's a small pocket of air. That air expands as it is heated by the hot water and "escapes" through the pores in the shell into the water as bubbles - making it look like the egg is breathing!

As easily as air can leave an egg, air can also enter an egg through those same pores, bringing different smells with it. Although the air can come out again through the pores, the smells stay inside. That's why if eggs are not stored in the egg carton you bought them in, they can take on the odours or tastes from other things in the fridge that smell - things like smelly meats, cheeses or onions. So, be sure to always keep eggs in their original egg carton in the fridge!

Saturday, February 23, 2008

Amazing detergent

Follow these instructions to experiment with colourful milk and learn about surface tension.

What you need

To do this experiment you will need

*a saucer
*food colouring (four different colours)

What to do

1. Fill the saucer with milk.
2. Add one drop of each food colour to the milk around the edge of the saucer.
3. Add one drop of detergent into the centre of the saucer.

What's happening:

The colours swirl and zoom around the saucer.

Milk stays together as one liquid because of surface tension. This acts like a skin and keeps the milk in a puddle. When you add the detergent, it breaks the surface tension of the milk in one spot.

The pull of the surface tension from the milk at the edge of the saucer causes the milk in the centre to move to the outside, taking the colours along with it.

The colours keep moving until the detergent stops affecting the milk.

Surface tension cause the colours to swirl.

Sunday, February 17, 2008

Getting the bird in the cage

Draw a picture of your favorite bird on a small index card. On another card the same size, draw a cage. Now tape the two cards, drawing sides out, on opposite sides of a pen. Spin the pen between your hands or fingers. Is your bird still free or did you catch it and put it in the cage?

Why does the bird appear to be in the cage?

It appears to be caged because of how your eyes and brain work. When you see the image of the bird, your brain holds onto the image for a short time--even though the image appears and disappears quickly. The same thing happens with the image of the cage. The two images actually overlap in your brain so the bird appears to be in the cage.

The technical name for this effect is persistence. It is what lies behind every movie and every TV program that you see.

Tuesday, February 12, 2008

Mobius strips

Cut a 5-cm strip lengthwise from a newspaper. Holding the strip out straight, give it a half twist (180 degrees) and glue the two ends together. Take a texta and carefully draw a line along the centre of the strip. Where do you end up? Is the line drawn on the inside or outside of the paper? Now cut the strip along the line you drew. How many chains do you get? Now try cutting a half-twist strip, one-third of the way from one edge.

Your piece of paper is called a Mobius strip, which is a shape described by a branch of mathematics called topology. When you twisted your strip, the inside and outside became one continuous surface. And when you cut the strip, it became one longer chain but still had only one continuous surface.

Try the experiment again and give the paper a full twist. Then try one and a half twists, and see what happens.