20 science favourites2.cwk (dr)

Prepared by Warren Bruce - Science Education Private Provider - Phone 03 308 9518Contact by Email : [email protected]

Thinking Being Creative Asking Questions Sorting QuestionsUsing Scientific Vocabulary Sharing Information Having FunInvestigating

BEING AWARE OF THE NATURE OF SCIENCE:

MUM,

DAD MADE

THE MESS

ON THE

FLOOR!

What you needWater crystals, Red, Blue and Yellow food colouring, teaspoon, straight side drinking glass, paper towels, 3 plastic disposable cups.

What do you do?Prepare the day before: Place a third of a teaspoon of water crystals into each of the 3 plastic disposable cups. Into each cup put several drops of food colouring i.e. blue in one, red in another and yellow in the third cup. Fill all three cups to the top with water and leave over night. (figure 1)

1. Pour out a small pile of each colour onto a separate paper towel. Allow the paper towel to soak up as much free liquid as they can. (figure 2)2. You need to layer the colours in you drinking glass. Work out the depth you need to put in the glass so that you end up with four layers of the same depth.3. the first layer to go in the glass is red, make sure you pack the crystals in as much as you can. The second layer is yellow, the third is blue and the last layer is red. (figure 3)4. Where different coloured water crystals are touching they will begin to 'bleed' together or diffuse into each other.5. After a few hours observe the colours in the glass. You can remember the order of the colours in a rainbow by using the acronym ROY G BIV. Each of the letters are the initial letters of the colours in a rainbow. Can you find out what they are? Record your findings in a diagram.6. The next day pour out the crystals onto a paper towel and separate them into colour groups. What would happen to the crystals if you left them for a day or two on the paper towel?

Activity#1MIXING COLOURS

If it reaches the dinner table, YOU win!TEACHING

NOTES


I Wonder....

• what would happen if you packed

the colours in a different order?

• what would happen if you tried

mixing different colours?

• I wonder how long a crystal would

take to dehydrate?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meanings for: HYDRATED, DEHYDRATED and SUPERABSORBANT

Tell someone at home about these words and what you have learnt about them.

What's happening here?As the crystals formed in the coloured water they absorbed that colour through the entire crystal. When the crystal are stacked in the glass the different colours begin to 'bleed' or diffuse into each other and after awhile you see an orange band beginning to appear between the red and yellow crystals. Initially the orange colour can be seen as the light passes through the red and yellow crystals but after awhile the orange band appears as the red and yellow crystal mix their colours.

You can use the water crystals that are available at garden centres that are mixed in the soil or potting mix to keep moisture available for the roots of plants. The crystals are a superabsorbant polymer. The small white granular material that looks like rock salt can absorb 150 - 300 times its own weight.

Always use with caution as you would any chemical in science.

figure 1 figure 2

figure 3




I DONʼT KNOW ABOUT THE MARK ON THE CEILING

Activity#2BLOOMING FLOWERS


NOTESWhat you needSaucer, pipette or half teaspoon measured spoon, water, coloured pencils or felts,scissors, cut out flower shapes from supplied template

What do you do?Cut out three or four flowers from the template sheet.

1. Colour in the petals on your flower, Remember felts will run.2. Fold the petals over one by one so that the coloured side is hidden. Measure 2.5mls (half a teaspoon) of water in the pipette and put in the middle of the saucer.3. Float your flower on top of the 2,5mls of water.4. Observe what happens to your petals. Don’t be impatient and watch closely. It will take about 30 seconds for things to have happened.


I Wonder....

• what would happen if you different

types of paper?

• what would happen if you used a

different liquid like lemonade?

• I wonder how long different papers

would take to open up the flower?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meanings for: ABSORBS, CAPILLARY ACTION, EXPANSION


What's happening here?Most dry paper will absorb water. There are fine gaps between the fibres that make up paper. The water is absorbed through these fine gaps into the paper. This is called CAPILLARY ACTION. The fibres in the paper expand slightly. This is why the coloured in petals begin to move when they get wet.




THIS IS A MESSY EXPERIMENT

Activity#3 SECRET MESSAGES

fig. 1 fig. 2


NOTESWhat you needWater crystals, 1 disposable plastic cup, glass bowl, a glass of water, pieceof writing paper and a permanent marker or pen.

What do you do?Prepare the day before: Place a third of a teaspoon of water crystals into the plastic disposable cup and fill with water. Leave overnight. (fig. 1 and 2)

1. Take the glass bowl and place it on the writing paper. Trace around the base of the glass bowl so that you end up with a circle. Lift the glass bowl and in the circle write a secret message using the permanent marker or pen. (fig. 3)2. Place the glass bowl over the secret message half fill the glass bowl with the crystals you soaked over night. Add enough crystals so that it is impossible to read the secret message . The size and depth of you crystals will determine how much you need to put in the bowl. (fig. 4)3. Invite a friend to try and read the secret message. Add the secret decoding liquid (the water) slowly pouring the water from the glass of water until the actual crystal are completely covered.


I Wonder....

• what would happen if you used

coloured crystals instead?

• what would happen if a message

was written on red paper and you

used red crystals? (see supplied

sheet)

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: REFLECTED LIGHT and REFRACTED LIGHT


What's happening here?The message initially looks all scrambled and unreadable because the light is scattered and reflected (bounced) by the water crystals. It is like looking through broken glass. When the water is added and the crystals are completely covered, the light rays pass straight through the water and the crystals without bouncing of the edges of the crystals or being scattered. The light goes straight in, bounces off the message, and goes straight out. It looks like you’re looking into a plain dish of water.

fig. 3

fig. 4




BEST DONE

AT A

FRIENDʼS

HOUSE!

Activity#4EXPLODING CANISTERS

TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needFilm canisters marked 1/4, 2/4, 3/4, with snap on lid (fig. 1), Alka-Seltzer tablets, water, watch or timer, paper towels for clean-up, a launching bowl like a 2 litre ice-cream container. and safety glasses recommended.

What do you do?1. Put on your safety glasses. 2. Divide the Alka-Seltzer tablet into four equal pieces. 3. Fill the film canister 2/3 full with water. 4. Place one of the pieces of Alka-Seltzer tablet in the film canister. Place the film canister upside down in the ice-cream container. What happens?5. This time you decide on the amount of water to put in the film canister. Do you think that it will make any difference?6. Make up your own experiment. What do you want to find out? How are you going to do it? What are you going to measure?7. Go ahead and experiment! If you really want to see the rocket fly, start by sealing the end of a cardboard tube with several pieces of duct tape or use a plastic tube with one end sealed. Divide the Alka-Seltzer into four equal pieces. Fill the film canister half full with water. Place one of the pieces of Alka-Seltzer tablet in the film canister and quickly snap the lid on the container. Turn the film canister upside down and slide it (lid first) into the bowl (fig. 2). Instead of the lid flying off, the bottom of the film canister shoots out of the bowl and flies across the room. Once you've mastered the technique, it's time to measure how long the film canister rocket takes to blast off. After each trial, write down the amount of water you used in the film canister, the size of the piece of Alka-Seltzer (this should not change), and the time it took to blast off. What amount of water mixed with a quarter piece of Alka-Seltzer produces the best rocket fuel? After you've determined the best amount of water to use, try changing the temperature of the water. How does temperature affect the speed of the reaction? Does warmer or colder water change the time it takes to blast off?


I Wonder....

• what would the results be if you

timed from putting the lid on to the lid

being blown off?

• what would happen if you had

water of different temperatures?

• I wonder what would happen if you

used a whole tablet each time?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meanings for: CHEMICAL REACTION, CARBON DIOXIDE GAS, PHYSICAL CHANGE , VARIABLE and CHEMICAL CHANGE


What's happening here?The first part of this experiment is just a variation of the classic Alka-Seltzer film canister rocket. The same principle is at work here. In both cases, carbon dioxide gas builds up so much pressure the lid is forcibly launched. With an Alka-Seltzer tablet, the CO2 is produced as a result of a chemical reaction. Try filling the canister half full of lemonade and put the lid on and shake it vigourously. With the lemonade the CO2 is produced as a result of vigourous shaking. This provides a good contrast between a physical and chemical change.

The fizzing you see when you drop an Alka-Seltzer tablet in water is the same sort of fizzing that you see when you mix baking soda and vinegar. The acid mixes with the sodium bicarbonate (baking soda) to produce bubbles of carbon dioxide gas. If you look at the ingredients of Alka-Seltzer, you will find that it contains citric acid and sodium bicarbonate (baking soda). When you drop the tablet in water, the acid and the baking soda react to produce carbon dioxide gas. The gas keeps building up until finally the top pops off.

We can thank Sir Isaac Newton for what happens next. When the build up of carbon dioxide gas is too great and the lid pops off, Newton's Third Law explains why the film canister flies across the room - for every action there is an equal and opposite reaction.

fig. 1 fig. 2




A REALLY MESSY EXPERIMENT

Activity#5 A CO2 SANDWICH

TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needSafety glasses, measuring cup and spoons, vinegar, baking soda, clip lock plastic bags (3 180 x 255 mm. and 3 100 x 155 mm.), paper towels.

What do you do?1. Use 3 large clip lock bags and put 2 tablespoons of baking soda in each. (fig. 1)2. Use the small clip lock bags putting varying amounts of vinegar. For example, fill one bag with 60 mL (1/4 cup) of vinegar, the next bag with 80 mL (1/3 cup) of vinegar and the last bag with 120 mL (1/2 cup) of vinegar.3. Leave the vinegar bag open and with a partner place each, one at a time, into the bag containing the baking soda. Someone can hold the bag with vinegar in it from the outside to stop it falling. (fig 2) over. Clip the large bag shut patting out as much air as you can.4. Make sure the baking soda bags are tightly sealed and put on your safety glasses.5. Put the bags on a table where it's okay for things to get a little wet and messy (outside tables would be good).6. Now get ready for the fun... Thoroughly mix the baking soda and vinegar. Use your EYES, EARS and HANDS to find out as much as you can about this chemical reaction. Leave the bag on the desk so that you can compare all three. (fig 3)7. Repeat with the other two bags.8. Make observations about how large each bag gets and how long it takes before you hear the giant POP!8. Literacy connection: How many good words can you write that describe what you see, hear and feel? Use the supplied grid template and work with a partner.


I Wonder....


warm water?

• what would happen if you changed

the amount of one of the ingredients

(variable)?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: ENDOTHERMIC, EXOTHERMIC, ACETIC ACID, SODIUM BICARBONATE, CARBON DIOXIDE


What's happening here?Sure, bubbling liquids and popping bags are fun, but what’s the science behind the exploding lunch bag? When you mix vinegar and baking soda, a chemical reaction takes place producing a gas called carbon dioxide (CO2). If you really want to impress your friends, use the chemical names for each of the ingredients. Acetic acid (that’s vinegar) plus sodium bicarbonate (baking soda) produces carbon dioxide gas and water. The bag puffs up because the carbon dioxide gas takes up lots of space, eventually filling the bag. If there’s more gas than the bag can hold… KABOOM! If you’re lucky, the zipper-lock seal will bust open, but the bag will not break. Now you can reuse the bag to make another CO2 sandwich. Wrapping the baking soda in tissue paper or separating the substances in bags is a clever way of slowing down the reaction.

fig. 1 fig. 2 fig. 3



What you needTea bags (the folded in half kind), an empty container for unwanted tea, matches and 15 cm x 15 cm piece of aluminium foil

What do you do?1. Remove the staple and string from the tea bag without tearing the bag.2. Carefully empty the tea from the bag into a container.3. Form a tube with the remaining tea bag.4. Place the tube on a fire safe table so that it is sitting on one of its open ends on a piece of aluminium foil.5. Light the top of the tube and allow it to burn down to the base. (fig. 1)6. OBSERVE what happens.

IʼM NOT ALLOWED BACK TO MY

FRIENDʼS HOUSE

Aluminium foil

Burning tea bag

Hot air rising

Cold air moving in forces the warmer air to rise

FLYING TEA BAGS

Activity#6


TEACHINGNOTES

If it reaches the dinner table, YOU win!


I Wonder....

• what would happen if you used an

ordinary tea bag?

• what would happen if you cut the

tube in half?

• I wonder if you could make a tube

out of tissue paper?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: DENSE AIR, LESS DENSE AIR, and EXPAND

Tell someone at home about these two words and what you have learnt about them.

What's happening here?As the flame moves down the tea bag tube, it heats the air in and around the tube causing the air to expand and become less dense. This causes the denser and cooler air to move into where the less dense air is and pushes the warmer air upwards. The rising air takes the very light ashen remains of the tea bag with it.

Fig. 1


BEING AWARE OF THE NATURE OF SCIENCE: JELLY BALLS

SUDDENLY

A HOLE

APPEARED

IN THE

FLOOR!

What you needJelly Balls (available from old $2 shops and some garden centres), clear drinking glass or glass bowl, water, ice cream container, copy of miniatureprint sheet, sheet of overhead transparency plastic.

What do you do?Pre hydrate the jelly balls the night before.

1. Place two or three hydrated jelly balls into a clear glass or bowl.2. Fill the container with water until the jelly balls are completely covered.3. Look carefully into the glass or bowl. Hold it up to the light. What can you see?4. Gently pour the water out of the glass or bowl over an ice-cream container through your fingers to catch the jelly marble. (Be careful with it as it will break easily)5. You can use these hydrated jelly balls in the same way as the water crystals in Activity #3. Try it!

Try Microscopy6. Take the sample sheet of miniature print and larger print. 7. Place the clear plastic sheet over the different font sizes.8. Carefully cut one of the hydrated jelly balls in half and place it flat side down on the plastic sheet.9. Move the plastic sheet over the different font sizes and look at the print through the cut jelly marble. Make jelly balls of different sizes.10. What happens?

Activity#7


TEACHINGNOTES



I Wonder....


coloured jelly balls and looked at

coloured writing? (you can colour

the jelly balls by hydrating them in

coloured water. Try red balls on red

writing.)• if you would see a yellow jelly ball

in yellow water?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: REFRACTED, MAGNIFICATION and TRANSPARENT


What's happening here?Jelly Balls:The jelly balls appear to have disappeared in the water and have absorbed a huge amount of water. When you look at the jelly ball in the glass or bowl you can barely see the outline of the jelly ball. The light is able to pass through the jelly ball just as it does through the water. There are no rough edges on the jelly ball to cause the light to be refracted (bent).

Microscopy:The cut jelly ball should have magnified the newsprint because the ball nw has a curved upper surface and the flat bottom was transparent. This shape bend (refracts) the light reflected from the object it in much the same manner as a glass-magnifying lens. The water-drop is a piano-convex lens (one surface flat, one surface curved out). The smaller the jelly ball, the greater the curvature of the upper surface and the greater magnification of the object underneath. The larger jelly balls do not magnify as much because there was not as much of a curve in the larger balls. A lthough the smaller drops magnified more, there was less area that could be seen.

fig. 1

Sometimes we need a magnifying glass to see small things. Can you find out how many planets in the solar system have moons? Why do moths fly at night if they like light so much, there is more light in the daytime? Often in space programmes you hear loud explosions taking place, what is wrong with

Sometimes we need a magnifying glass to see small things. Can you find out how many planets in the solar system have moons? Why do moths fly at night if they like light so much, there is more light in the daytime? Often in space programmes you hear loud explosions taking place, what is wrong with this?

fig. 2



BEING AWARE OF THE NATURE OF SCIENCE: MAGIC BEAN (A Fair Test)

DAD THREW

IT OUT BUT

FORGOT TO

OPEN THE

WINDOW!

What you needCopy of Bean template photocopied onto photocopier card, cellotape,marble, scissors, a ramp (a board covered with a tea towel)

What do you do?Construct a Magic Bean according to the instructions on the supporting sheet.

1. Place the constructed Magic Bean at the top of the ramp by resting one curved end on the ramp covered with the tea towel. Let the Bean go and observe what it does. (fig 1)

You are now ready to carry out a Fair Test Investigation.2. Decide what you could change about your Bean.3. Decide what you will measure.4. Make a second Magic Bean by changing one thing. (Change only ONE variable)5. You are going to compare the first Bean with the second Bean. What question will you be trying to find the answer to?6. Make a Hypothesis (what do you thinks is going to happen? 7. Now it is time to gather data. Test the original bean at least 5 times and record your data . Then take the second bean and test it five times and gather your data. (Make sure the bean is released in the same way f the same starting point each time)8. Now that you have carried out all 10 tests, look for patterns in your gathered data.9. Share your findings with someone.

Activity#8

TEACHINGNOTES



I Wonder....

• what would happen if you made

the Bean out of a different coloured

piece of cardboard??

• what would happen if you tried

different ramp surfaces?

• Would the angle of the ramp make

a difference?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: FAIR TEST, VARIABLE, HYPOTHESIS


What's happening here?This activity is all about carrying out a Fair Test. The things here to be looking at are: • Having a question• Making an Hypothesis• Controlling all variables except one.• Gathering data from repeated tests• Looking for patterns in the data• Linking their finding to the question• Sharing their findings with the class.

fig. 1


BEING AWARE OF THE NATURE OF SCIENCE:WHERE HAS IT GONE?

I can explain

why the door

is on the

floor!

What you needA black PILOT Frixion pen, a black BIC click pen, candle and matches,paper to write message on.

What do you do?1. Write a secret message using the black BIC click pen.

2. Write over the top of your message using the Frixion black pen. You can draw or scribble over the original writing. I find writing over the top best as you don’t want to be able to read the original message.

3. Give your secret message to a fiend.

4. They will need to to reveal the secret message. There are several ways to do this: Run the paper , writing facing up, over the top of a candle flame. (ALWAYS HAVE AN ADULT HELPING WHEN USING FIRE) Holding it over a toaster will work too.

5. Now that you are amazed send a secret message back to the writer.

6. Having made the scribble or writing disappear, put the paper in the freezer for half an hour. What happened?

Activity#9


TEACHINGNOTES



I Wonder....

• what would happen if you

laminated your work written using a

frixion pen?

• if this would work with other

papers?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: FRICTION and THERMOCHROMIC


What's happening here?The friction pen uses ink that is sensitive to heat. At temperatures that range between -10°C and 60°C, the ink will appear black when writing on paper. But when local temperature exceeds 60°C, like when held near a heat source or when friction is concentrated on a certain spot, the ink becomes clear.

This specially formulated ink is called thermochromic ink and can actually be formulated into different colours and to change colour at different temperatures. Believe it or not, this probably isn't the first time you've seen or used thermochromic ink. This special ink has been used in mood rings and heat sensitive labels. Additional InfoNow, what if you spent an extraordinary amount of time disguising your secret message and your coverup ended up being quite the piece of art? It's all right, your ink can come right back, making your coverup beautiful again. Stick your secret message paper in the freezer! Once the local temperature on the ink drops below -10°C, the ink will once again turn black. Reappearing art!



GEE EGG IS

HARD TO

GET OFF

CARPET

MUM!

What you needCardboard toilet tube, paper picnic plate, large preserving jar, water and paper towels, egg and a ball (make sure the jar is wide enough for an egg or small ball to drop into it)

What do you do?1. Fill the preserving jar half full of water.

2. Centre the picnic plate on top of the jar.

3. Place the cardboard tube upright in the centre of the plate.

4. Place an egg on top of the tube. (fig. 1)

5. It might be a good idea to start with a ball.

6. With a sharp hit knock the the plate away off the jar by hitting on the edge. (do not follow through and knock the jar and everything else onto the floor. You will have a real mess to clear up. Perhaps this is a good one to try at a friends house!)

7. There is not a great deal of friction between the jar and the picnic plate so it should be easy to knock away from the jar. If all goes well gravity should allow the egg to drop neatly into the jar. Inertia: The tendency of an object to stay at rest (the egg sitting on the tube) or to remain in motion until a force act upon it (your hand causes the tube to fly out and the force of gravity takes over, causing the egg to fall)

Activity#10 INERTIA


TEACHINGNOTES



I Wonder....


taller tube?

• how many jars and eggs you could

do at one time with the tubes sitting

on one tray?

• I wonder if the amount of water is

important?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: INERTIA, FRICTION and GRAVITY


What's happening here?Credit for this one has to go to Sir Isaac Newton and his First Law of Motion. He said that since the egg is not moving while it sits on top of the tube, that’s what it wants to do - not move. You applied enough force to the pie pan to cause it to zip out from under the cardboard tube (there’s not much friction against the drinking glass). The edge of the pie pan hooked the bottom of the tube, which then sailed off with the pan. Basically, you knocked the support out from under the egg. For a brief nanosecond or two, the egg didn’t move because it was already stationary (not moving). But then, as usual, the force of gravity took over and pulled the egg straight down toward the centre of the Earth.Also, according to Mr. Newton’s First Law, once the egg was moving, it didn’t want to stop. The container of water interrupted the egg’s fall, providing a safe place for the egg to stop moving so you could recover it unbroken.

Fig. 1


BEING AWARE OF THE NATURE OF SCIENCE: WILL IT HIT THE FLOOR?

THE HOLE JUST KEPT GETTING BIGGER!

What you needA long shoelace, a pencil, keys or hexagonal nuts in place of the keys,a washer.

What do you do?1. Tie the keys or several hexagonal nuts to one end of the shoelace and a single washer or a single hexagonal nut to the other end. (figure one)

2.. Hold the washer and let the keys hang over the pencil which you need to hold horizontal, as in the photo. Allow the keys hang about 10cm over the pencil.(figure two)

3. Ask if anyone would like to predict what will happen when you let go of the key-ring. If no-one responds, ask who thinks the keys will stay where they are or hit the floor?

4. Let go of the washer. The washer should spin around the pen several times causing the keys to remain hanging from the pencil.

Activity#11

figure one

figure two


TEACHINGNOTES



I Wonder....

• if the length of shoelace hanging

over pencil will make a difference?

• what would happen if I used a

longer shoelace?

• I wonder if by changing the weights

I can get it to wind more times

around the pencil?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: GRAVITY, PENDULUM, and FRICTION


What's happening here?It is difficult to predict the outcome and it is difficult to explain unless you were able to film it at very, very slow motion. When you let go the shoelace the heavier end will fall towards the floor while the lighter end is pulled upwards towards the pencil. The lighter end which you let go has begun to swing like a pendulum and as it the shoelace gets shorter by the millisecond and the pendulum swings faster and faster. Finally the pendulum is swinging so fast that it swings over the top of the pencil several times and the friction between the shoelace and the pencil is enough to stop the heavier end hitting the floor.



MUM,

THE CAT

HAS a singed

TAIL!

Activity#12WHATʼS BURNING HERE?

figure three figure four


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needTwo candles (do not have to be tea light candles), Clothes peg, Matches

What do you do?1. Light both candles. (figure one)2. Hold a match in the clothes peg and light it in one of the candle flames and allow the match to burn until it nearly reaches the end of the clothes peg. Blow the match out carefully. (figure two)3. When the match is out, hold it still using the clothes peg, and put it in the flame again. What happens? 4. Extinguish the flame of ONE candle. (figure three)4. Dip the end of the match in the liquid wax that is in the top of the candle that has no flame. (figure four)5. Hold the match, you dipped in wax, in the flame of the other candle. What happens?6. Why does this happen?

figure one

figure two


I Wonder....

• what would happen if you tried this

using a kebab stick?

• what would happen if you let the

burnt to cool before dipping it in the

molten wax?

• I wonder what would happen if I

dipped the burnt match in cooking oil

instead of wax?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: WAX VAPOUR, CHARCOAL and CAPILLARY ACTION


What's happening here?A candle flame is burning wax vapour. A burnt match is really a piece of charcoal and contains no fuel to burn and will only glow in a flame. By dipping a burnt match in liquid wax and putting it into a flame heats the wax until it melts and vaporises. The match appears to be burning again.

When you dip the match in the molten wax, if you watch carefully toy might see the molten way travel up the burnt match through capillary action.

Burning a match is a chemical change and because it is releasing heat and light and changing the match from wood to ash.



THE CEILING

JUST

STARTED

TO DRIP!

What you needTwo telephone directories that have at least 100 pages

What do you do?This uses nothing but the two directories.

1. Place two directories beside each other with the opening sides facing each other.

2. You need to interleave the pages of the two directories. The more individual pages you interleave the better.

3. The interleaving should overlap to about the middle of the page. Rub you hand over the top of the top book smoothing the pages down.

4. When you are ready get two people to grab the spine of one of the books each.

5. Ask them to pull on the spine to separate the two books.

Activity#13THE POWER OF FRICTIONThinking Being Creative Asking Questions Sorting Questions

Using Scientific Vocabulary Sharing Information Having FunInvestigating

TEACHINGNOTES



I Wonder....

• what would happen if you

interleaved the pages in groups of

six pages?

• what would happen if you tried an

exercise book?


overlap the pages to about a quarter

of a page?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: FRICTION

Tell someone at home about this word and what you have learnt about it.

What's happening here?The thing that holds the two books together is simply good old friction. Friction is the name we give to the force that opposes the movement of two surfaces in contact. You would hardly notice this between two sheets of paper. But increase this to 100 pages the friction becomes almost impossible to separate the pages.

The friction depends on the interleaved surfaces.

Friction can useful in some situations and not useful in others. Think about the friction you need on your shoes when playing basketball and then when trying to screw a screw into wood.



WE PUT

THE CHAIR

OVER THE

HOLE IN THE

CARPET!

Activity#14SALTY CIRCUITS

1. Connect one end of a connecting wire to the positive (+) side of the battery. Connect the other end to the long leg (+) of the L.E.D. (figure one)2. Connect one end of a connecting wire to the negative (-) side of the battery. Connect the other end to one side of the folded paper towel. (figure two)3. Connect one end of a connecting wire to the short leg (-) of the L.E.D and the other end to the opposite side of the towel to the other connecting wire. (figure three)4. The paper towel is acting as an insulator and will not allow the electricity to pass through it.5 Pour some water, carefully on to the towel until water spreads across it touching where the connecting wires are attached to the towel. (Observe what happens to the L.E.D) 6 While watching the LED get someone to sprinkle salt over the wet paper towel between the two clips. (What happens to the L.E.D?)


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you need9v battery, L.E.D, Water, Salt, Paper towel, 3 connecting wires with clipson each end

figure one

figure two

figure three


I Wonder....


different powders?


different liquid?


used different paper?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: L.E.D, INSULATOR, CONDUCTOR and CIRCUIT


What's happening here?The dry towel acts like an insulator and will not let the electricity flow through it and complete the circuit. When you wet the towel the electricity can travel through the towel completing the circuit and lighting up the LED (i.e. it is now able to conduct electricity). There is still a little resistance in the water. When you add salt the water resistance is lessened even more and you should notice that the LED glows a little brighter when the salt is sprinkled over the wet towel.

Try it again with a dry towel.



GRANDDAD

TRIED TO

CLEAN THE

CEILING!

What you need3 120mm x 120mm mirrors, tape, laser pointer or torch

What do you do?Prepare the three mirrors by taping them together. (fig. 1)

1. Look into the corner of the reflector. Notice that your reflection is reversed to what you would see in a regular mirror. In other words you see yourself as others see you. To prove this point to your left eye, your image will also point to the same eye. Try it in the mirror at home on the wall and you will find you are pointing to the other eye.2. Close one eye and look into the corner of the reflector. What do you notice? Close the eye open the other. What do you notice now?3. Look into the reflector’s corner with both eyes. One eye will be closer to the corner than the other. This is your dominant eye.4. Try shining a torch into the corner reflector. Best if the torch has a focused beam. Slowly walk in front of the reflector. What do you notice about the reflected beam of light? The light should always be reflected straight back to you no matter where you are standing with the torch.

Activity#15CORNER REFLECTOR

Fig. 1


TEACHINGNOTES



I Wonder....


smaller mirrors?

• if bigger mirrors would work

better?• if it would reflect coloured light

beams?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: REFLECTED LIGHT


What's happening here?When 3 mirrors are arranged to form a corner, each mirror is at right angles to the other two, a beam of light is bounced back on itself. The beam makes three reflections, one reflection at each mirror and is then reflected back to its source. This is a unique property of a corner reflector.

A large number of corner reflectors make up the reflectors you see on the side of the road and down the middle of many of our main roads. There can be up to 800 tiny reflectors making up each reflector you see on the road. They reflect the light from a car headlight directly back to the car. The beauty of these reflectors is that they do not have to be carefully aligned when they are put in place. As long as they face roughly down the road they will always reflect car headlights straight back to the oncoming car.

Find out about: Lunar Corner Reflectors, uses in Surveying, how Reflectors are used in shops, reflectors on bicycles, how the military use reflectors, how they are used on ocean going yachts.

Look into the corner reflector with both eyes open. The eye closest to the corner is your dominant eye.

Next close one eye. You will see that the open eye is right in the corner of the reflector. Now open the eye you closed and close the eye you had open, you will discover that the open eye is right again in the corner.


BEING AWARE OF THE NATURE OF SCIENCE:PUT THAT FLAME OUT!

GRANDMA

SAID IT

WOULD BE

OK IN THE

LOUNGE!

Activity#16


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you need2 litre ice-cream container with a hole in one side about half way down andblocked with a cork., 3 candles (one just below the height of the ice-cream container, the other two both shorter but different heights, matches, Vinegar, Baking Soda,blu tak

WARNING: Emphasise the dangers of matches and candles.

What do you do?1. Fix three candles to the bottom of the icecream container using blu tak. The candles should be three different heights (see above). Make sure the cork is in the hole.

2. Light the candles.

3. Add a tablespoon of baking soda in a heap to the bottom of the icecream container. PREDICT what you think will happen before you add the vinegar.

4. Pour 100ml of vinegar into the bowl.

5. OBSERVE what happens. Can you EXPLAIN why this happened?

6. Empty out the contents.

7. Replace the three candles and a tea light candle outside the container under the hole (see photo Fig.1). PREDICT what YOU think will happen.

8. Repeat above using the ice-cream container without the cork in the hole.

9. OBSERVE what happens this time?

10. EXPLAIN why this happens.


I Wonder....

• what would happen if all the

candles were the same height?


twice the amount of baking soda?

• I wonder if using twice as much

vinegar would make a difference?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: CHEMICAL REACTION, CARBON DIOXIDE and INCOMBUSTIBLE


What's happening here?The chemical reaction between the vinegar and the baking soda produces carbon dioxide and water vapour. Carbon dioxide is more dense than air and is incombustible (does not support combustion). Being more dense than air, the carbon dioxide rests below the air in the bowl. Since the carbon dioxide is continually produced, it pushes the air out of the bowl as it fills up the bowl. The candles go out because carbon dioxide level is increasing and is incombustible (does not support combustion). The shortest candle will go out first followed by the taller candle, which shows that the bowl fills with carbon dioxide from the bottom up. Some fire extinguishers use carbon dioxide to extinguish flames.

When you try the experiment with the cork removed, as the carbon dioxide reaches the bottom of the hole, it pours out and puts out the tealight candle. The taller of the three candles which is above the hole continues to burn as it is above the carbon dioxide. The hole allows the carbon dioxide to pour out and it does not build to the same level as when the cork was in the container.

Fig. 1



I TOLD DAD WE SHOULD DO IT OUTSIDE

Activity#17FLOATING TABLE TENNIS BALL


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needTwo disposable Plastic cups, table tennis ball, pipette, hair comb, piece of clothand water

What do you do?1. Fill a plastic cup almost to the brim with water, but not over full. The surface of the water should be concave shaped like a plate. You need to observe that the water is slightly lower in the centre than at the edge.

2. Carefully place a table tennis ball on the surface of the water. Wait until all movement ceases and OBSERVE where the ball is sitting. (fig. 1)

3. Add water to the cup until it is nearly overflowing and this is a convex shape. The water level is above the edge of the cup. This is the opposite of concave.

4. OBSERVE what happens to the ball this time.

5. Take the comb and rub it vigourously on a cloth or some clothing, a woollen jersey is ideal.

6. Take the comb and without touching the table tennis ball watch what happens to the ball.

7. Can you pull the ball all over the surface of the water?


I Wonder....


different small ball?

• what would happen if you tried this

using milk?

• I wonder what will happen if you tilt

the cup slightly?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: CONCAVE, CONVEX, and MENISCUS


What's happening here?On a concave meniscus (when the highest point is at the side of the cup) the ball will float to the highest point which is at the side of the cup whereas on a convex meniscus (when the highest point is in the middle of the cup) the ball will float in the centre of the cup where the highest point is. In the other words the ball always floats to the highest point.

Rubbing the comb on cloth charges the comb with static electricity. When the comb is bought near the neutral table-tennis ball it affects the surface of the ball, because it too is made of plastic. The charge on the comb (+) attracts opposite charges (-) in the ball and they cluster at the surface. Unlike charges attract and hence the comb and the ball attract each other. Providing you do not touch the comb to the ball, you should be able to pull the ball all over the surface of water in the cup.

FLOATING TABLE TENNIS BALL

fig.1



THIS IS A MESSY EXPERIMENT

Activity#18 ANOTHER SECRET MESSAGE


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needThe red prepared sheets (run the red sheets through the photocopier, putthese sheets in the photocopier tray and over print them with the light grey writing on the second sheet), 3H pencil, glass with a clear bottom, red food colouringand water

What do you do?.

1. Put about a centimetre of water into the glass. Add two small drops of red food colouring.

2. Place the glass over the red coloured shapes that have the grey writing overprinted on them. What do you notice? (fig 1 and 2)

3. Try a clear red shape and write a message using the 3H pencil.

4. Place the glass over the red shape you wrote on. What do you notice?


I Wonder....


blue filter to look at something written

in yellow on a blue surface?

• What other colours could you use

to write secret messages?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: FILTER,


What's happening here?The red filter blocks out the red light and only allows the grey to come through to your eye.

SCIENCE CAN BE FUN LOOKING FOR ANSWERS TO THINGS THAT PUZZLE YOU

Fig 1 Fig 2



BEST DONE

AT A

FRIENDʼS

HOUSE!

Activity#19PINCHING COLOURS


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needPrepare some coloured gels by mixing clear hair gel with yellow food colouring, then some more gel and blue food colouring and gel and red food colouring, you will need some A5 clip lock bags and paper towels.

Make a literature connection by using Mouse Paint by Ellen Stoll Walsh ISBN 0152002650, Colour Dance by Ann Jonas ISBN 0688059902, Little Blue and Little Yellow by Leo Lionni ISBN 0688132855 or White Rabbit’s Color Book ISBN 139780753452547

What do you do?

1. Place a tablespoon of each coloured gel in an A5 clip lock bag. Try and put one colour in each corner and the third in the middle. (fig. 1)

2. Make sure you squeeze as much air out as you can before clipping the bag shut.

3. Then pinch and mix the goo to your heart’s content. (fig. 2)

4. Now, watch as the colours begin to blend from primary to secondary colours! The blue and yellow are becoming green, the red and yellow are turning orange, and the red and blue are blending into purple! Soon your bag will take on a soft, stained-glass effect.But... anyone who has spent time with a child knows that they are not going to gently pinch the colours together slowly and revel in the beauty... NO they are going to grab that bag and after a nanosecond of gently mixing will squeeze and squish that bag of goo! Wait! Before you fuss that the activity is ruined, stop and hold that bag of squished up gel to the light. LOOK! The colours have created gorgeous swirling patterns! This activity offers a new twist to a time-tested experiment and is also great for strengthening the fine motorskills of small fingers.


I Wonder....

• what would happen if you put more

of one colour in the bag?

• what would happen if you made

some different coloured gels?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: SECONDARY COLOURS and PRIMARY COLOURS


Now Try This...Dust off that old overhead projector to set up your own colour mixing theatre and bring a whole new level of WOW to the activity! Pinch and Mix the bags of goo while they are laying flat on the projector surface. Watch as you mix the goo for a brilliant show of colour and light. No overhead projector... no problem! For a similar effect, try holding your bag of goo up against the window while you blend.

Now that you have mixed and mixed and mixed, you are wondering what to do with a bag full of dreary-coloured goo. The answer is.... take the activity to the next level! Lay the bag of goo flat on the table. Smooth the goo evenly inside the bag. Now, use your finger as a writing tool and practice forming letters and numbers! No need for erasers with this writing tool, just smooth the goo inside the bag and begin again!What's happening here?Not only does this Pinch and Mix activity help drive home the idea of primary colours blending into secondary colours, it offers so much more! It gives children that needed time to wonder, discover, and explore. As soon as their bag becomes all one colour the children are guaranteed to want to do it again! This time, predict what colour your bag will be when you are finished mixing. Will it be brown, black, grey...? Why is it different each time? The answer is in the balance of colours added to the bag. If you add more red and yellow than blue, your bag will become a shade of brown. If you use more blue than yellow and red and your bag will end up a shade of black. So, how does this apply to real life, you ask? Where is colour mixing found other than an artist's studio? The answers are right outside your window! What happens when the sun appears during a rainstorm?...a rainbow!

Fig. 1

Fig. 2



I DONʼT KNOW ABOUT THE MARK ON THE CEILING

Activity#20PURSUIT RACING


TEACHINGNOTES

If it reaches the dinner table, YOU win!What you needA hair dryer, cotton reel (the cyclist), Piece of cardboard 15cm x 6cm folded in half to represent the front cyclist (glue a cycle on each side of the folded card),a ruler.

What do you do?

In some cycle races pacing is allowed. A pacer is another cyclist that gets out in front for the others to follow closely. By getting in close the cyclist that is following gets into the slipstream created by the front cyclist.

1. Use a cotton reel to represent the cyclist.

2. Tape the piece of cardboard in a V shape to the table about 10 cm from the edge, this represents the ‘pacer’.

3. Use the hair dryer to create the rushing wind. Hold the hair dryer level with the table and about 10 cm in front of the cardboard ‘pacer’.

4. Place the ‘ cyclist’ (the cotton reel) 20 cm behind the cardboard (the ‘pacer’).

5. Gradually move the ‘cyclist’ 1 cm at a time nearer the ‘pacer’.

6. Observe what happens. At what distance behind the ‘pacer’ does the slipstream take effect?


I Wonder....

• what would happen if the ʻpacerʼ

was longer?

• what would happen if the ʻpacerʼ

was taller?

• what would happen if the angle of

the dryer was changed?

DEVELOPING SCIENTIFIC VOCABULARY:Find the meaning for: SLIP STREAM and AIR CURRENT


What's happening here?

Team pursuit is much more hectic than individual pursuit. Teams of four racers work the same distance, with the same goal in mind, but the fastest three racer's times from each team are what determines their overall time. If all three racers break it through the other team, the slower team loses the race. The teams will ride in a straight line to reduce the drag being placed on the riders in the back. Whoever rides in the front has to do the most work, and many times that racer will peel off of the pack towards the end of the race so his/her team mates can shoot forward with fresh legs. As you can imagine, this is very dangerous for a team of three or four riders to over take another team, but that is what makes these races so exciting! As of this writing, this race is still scheduled to be included in the 2012 Olympics.

20 science favourites2.cwk (dr)

Education

teaspoon of water crystals

d h t colours

p p lemonade t p

w o u w h

p e r sy p e t w o u

mls of water

y ld t h e c t w o u

paper towels