The big girl received an art book for Christmas. Most of it is way too old for her, but she loves picking things out and then we get to work out how to modify them for her.

She wanted to try marbling, but we had a few problems to solve so we tried lots of different ways. The idea of simple marbling is to have partial layers so the paper contacts different materials and colours. The explanations in the book are for using oil paints on water, which we didn’t have, so we tried lots of other ways to make our layers.

Attempt 1:

We used some of our acrylic paints from squeeze bottles into a tray of water. Too thick, we ended up with worms that melted onto the paper as they dried.

Attempt 2:

We tried to thin the acrylic paint with oil and vinegar because we didn’t have any spirits. Neither worked, although the girls had a good time trying to mix them and seeing them break up into little balls. I didn’t try to teach them ‘insoluble’

Attempt 3:

We swapped the concept over – instead of trying to get coloured oil floating on clear water, we went for clear baby oil on coloured water using food colouring. Success at last!

Except of course you can’t stop there. What happens if you use different colours? Different amounts of oil? Are blobs different to more spread out? What about trying cardboard or foam rather than paper?

You can see why we’re still doing this a week later. Have you done marbling? Have you tried different ways of doing a favourite activity? 

Location:

Slab has been well prepared, very smooth and level on a hard substrate. Block is minimum size, house too close to front boundary.

Floorplan:

A simple rectangle with only one room and firepit in the centre for cooking. Entrance centre front is decorative only, 6 windows give adequate light and ventilation but difficult to crawl through, not weatherproof.

Construction:

Walls, roof, door and chimney all constructed from gingerbread. Thin, smooth and even but rather brittle, I have concerns about its strength, load bearing ability and waterproofing.

Joints appear to be made of a sugar and protein mix. The long protein chains help strengthen and bind the mortar. Joins are uneven, some are coated inside and out and others inside only. Walls and roof are crooked, flashing on the roof is a solid seal but very overdone. I have concerns about how long the joints will last as they are not reinforced.

The construction is solid, but it is through use of excess materials.

Conclusion:

The house is decorative and appears to be habitable immediately, however it is very unlikely to last. I predict it will come to pieces in a matter of days. Not recommended as a long-term investment.

I’m sure it will be delicious.

Do you have any idea how many patterned, textured surfaces you have around your home? Hundreds. Trust me.

Obligatory Christmas tie-in – use rubbings to make wrapping paper, just use crayons or pencils on butcher’s paper. Kidlet’s creatively entertained and personalised paper as elaborate as you want.

Learning about materials is a good way for little kids to learn about, well, materials. It’s a great start because they are something they know and are familiar with, and they can easily see and feel differences in their own clothes. We are always having discussions about whether clothes will be too hot or too cold, it’s an easy way to link what something is made of and what it is used for.

In the past, making clothing was a huge part of everyday life. Growing flax, cotton or running sheep for wool was a major part of agriculture, then preparing and colouring fibres, spinning yarn and finally weaving or knitting to produce cloth took up a huge part of a family’s productive time. It used to be part of a servant or solider’s contract, that they would be given a certain amount of clothing every year as part of their payment.

Now, we go to the shops and buy whatever we want. Much of the time we don’t even know what it is made of or how it is made, and when we are finished with it it might get passed on, sold or donated or it might end up in the bin.

I’m not saying this is a bad change – I’m sure we manage to do other productive things with the time! But weaving, plaiting and knitting are still fun activities for kids to do, they develop find motor skills, let them be creative, and let them make connections with the world around them.

Plaiting

Big girl has gorgeous long hair, and being at a typical primary school with regular nit plagues we generally plait it. She adores ‘playing hairdressers’ and has learnt to plait. We have some novelty yarns and she has used them to make simple head bands and scarves just by plaiting them. She’s working on some for her friends for Christmas presents.

 Weaving

This is a fairly new one but the little girl especially is loving it. We haven’t got onto yarns yet – you can see at the top we’ve been grass weaving. I’m actually amazed at the number of things around our house that can be used as a loom, there are fences, gates, cages, lattice and random metal grids. I know not everyone has inherited all of these things at their home, but you probably have something! If not, plastic garden lattice will work.

We have lots of long grass in the paddock but you could use wool, ribbons, bark or sticks depending on the size of your loom. The grass is relatively stiff which is good for little fingers and we found it worked best starting at the bottom. Then you just need to pull it up and tuck it under every second wire. Should I mention the science involved in finding the best technique and testing different materials?

It’s something we only do for a few minutes at a time, but we’re adding to it and growing a design. You can see some dry grass in the photo, I can’t wait to see how it looks as more dries out and we keep adding fresh. When the little girl has practised more or depending on the big girl’s co-ordination I want to add some bright wool as well, we could end up with something very dynamic.

How much do you know about water? Check back to the quiz for the questions.

1.     Generally the solid form of something is heavier than the liquid because it’s packed together more tightly and there’s more in it. But ice is less dense than water, which means for the same volume there are less molecules in it. This makes it lighter and it floats on top (which, incidentally, does things like making life possible in lakes).

The reason it is less dense is because of something called hydrogen bonds. Water molecules are made up of one oxygen and two hydrogen atoms, and when it is cold the hydrogens can form a bond with an oxygen from another molecule. This means they make a stiff crystal lattice and moves them further apart, making ice less dense.

Water molecules in ice showing hydrogen bonds (grey dotted lines).

Hydrogen bonds in water are also important for life in another way – they make water molecules ‘stickier’ and mean they need more energy to boil, and so a higher temperature. This very big gap between freezing and boiling where we have liquid water is what gives us the ‘space’ for life. And I’ve even found a ‘Hydrogen Bond Song’ down the bottom

2.     Yes, there is water on the moon in the form of ice. Generally the problem on the moon is that when it is in direct sunlight it is extremely hot and anything like water would have boiled off into space long ago. But there are some craters in the southern polar region that are so deep they are always in shadow. This makes them the coldest place in the solar system and means that ice has survived there.

3.     The Dead Sea is the lowest place on earth that isn’t covered by water – the shores are 423m below sea level. It is called the Dead Sea because it is so salty that very little can live there, only small numbers of algae and bacteria. It’s more than 8 times saltier than the ocean. The reason it is so salty is because of the low elevation – water flows in but it can’t flow out because there is nowhere else to flow down to. It evaporates in the heat, leaving its burden of minerals behind.

In addition, the area is covered in halite or rock-salt, including the biblical Mount Sodom. Millions of years ago the Dead Sea was a long inlet of the Mediterranean. It’s in an active fault zone where Arabia and Africa are moving apart and the movements cut it off from the rest of the sea. Over the millennia the sea water evaporated and left large salt deposits underneath what would become the Dead Sea.

The Dead Sea is shrinking because of diversions of its inflow, the Jordan River. There are plans to use water from the Red Sea and desalinate them for use in the surrounding areas, then pump the waste brine into the Dead Sea to help maintain it.

4.     You don’t need to drink 8 glasses of water a day. You do need roughly a litre to replace what is lost through urine, sweat and breathing, but a lot of that can come from food. In fact with a water rich diet of things like fruits you may not need to drink at all. Anything extra just works your kidneys and bladder, it doesn’t clear extra toxins out of you or anything like that.

One of the easiest ways to track your hydration level is through headaches. If you get dehydrated it lowers the volume of cerebro-spinal fluid around your brain and spinal cord ever so slightly. This irritates the nerves and causes a headache. If you have a headache with no obvious cause, a glass of water is the first thing to try.

5.     The picture above is a Coolgardie Safe. This was a way of keeping food cool and fresh with no electricity. It wasn’t as good as an ice-chest but in the goldfields it made a big difference to the taste and safety of food.

The sides are hessian and the container at the top held water, which dripped down onto the hessian and wet it. Then as the water runs down it cools by evaporation. It takes energy to evaporate water, which comes from the surroundings and cools them. Simple but effective.

I‘ve tried to make meringue a couple of times and it hasn’t worked, so that was probably a sign that I shouldn’t have done this. Or at least that I should have tried it several times before putting it in the blogging schedule. But given trips to Melbourne and husband travel and another trip to Sydney coming up, we only got one go at it. And while I can tell you the reasons it should work theoretically, the reality was somewhat different.

But being a science blog and all, this is just an opportunity to work out what went wrong! Seriously! And the girls enjoyed it. So read this bearing in mind that if you know how to make successful meringues or have an idea how to get it to work, please let me know. There’s enough for a lot of experiments in a tub of icecream.

Materials

These amounts made far too much meringue for us, but given that I’m obviously not an expert I’m not going to modify the recipe. You can mess it up all on your own. I suspect that if you were to use only one or two eggs the right amount of salt and cream of tartar would be ‘a pinch.’

• 3 egg whites
• 1/4 tspn cream of tartar
• 1/4 tspn salt
• 1/2 tspn vanilla essence
• 1 cup castor sugar
• Large plain biscuits
• Icecream

Method

1. Let the eggs come to room temperature and separate the whites and yolks. 
2. Put the whites in a bowl along with the cream of tartar, salt and vanilla.
3. Whisk or beat the mixture until it makes stiff peaks.
4. Slowly add the sugar a spoon at a time while continuing to beat until the mixture is thick and glossy.
5. Space the biscuits on a lined tray. Put a small spoon of icecream on each one.
6. Completely cover the icecream with the meringue mixture. Make sure there are no holes.
7. Bake in a cool oven 110 degrees C (225F) for about an hour.

What should happen

Cream of tartar is actually tartaric acid, it produces carbon dioxide and helps aerate the meringue. When egg whites are beaten the protein forms long chains that tangle and surround air bubbles, which is what makes them stiff. As they are cooked the sugar hardens and crystallises but it is spread throughout the mixture, so it all goes hard.

The air and carbon dioxide bubbles act as insulation, which stops the heat getting through to the icecream inside and should stop it from melting.

Except

I have several ideas what might have gone wrong. The meringue was still chewy, the biscuits soggy and the icecream everywhere.

• I’m pretty sure I didn’t use brand new eggs, that could have stopped them forming peaks but they seemed to work ok.
• Possibly we didn’t whip enough, I was very conscious of the girls’ attention span and may have rushed making it.
• The sugar didn’t really dissolve, not being experienced with meringue I don’t know if it is supposed to dissolve or just mix through.
• I think the gingernuts were a problem. They do tend to go soggy where other biscuits don’t, so maybe they let the icecream out. Maybe try with large choc chip biscuits or milk arrowroot?
• Getting it all together was difficult. Between children ‘helping’ and extremely sticky meringue mixture I probably left gaps.
• I still have no idea how to cook the meringue properly – longer? higher temperature? I don’t know how to cook the inside!

Over to you – I’d love to get this to work, so does anyone have a foolproof meringue cooking technique? Or the perfect base? Who wants to have a go and then tell me how to do it?

Water, water everywhere, nor any drop to drink.

1. Why does ice float?
2. Is there water on the moon?
3. Why is the Dead Sea called that?
4. Do you need to drink 8 glasses a day?
5. And what’s the piece of Australian memorabilia in the picture, and what the heck does it have to do with water?

Answers here!

At first this sounds really weird – we use glass for windows so we can see through it, but we also use glass for mirrors and we can see ourselves. Why does it act differently in different things?

The answer is that it isn’t really the glass that makes the mirror.

Good quality glass is transparent and we can see through it clearly. This is why we use it in windows, and also its job in mirrors. Because the glass isn’t what makes the reflection we see, it is only there to protect the metal behind it and let us see through it.

If you have a close look at the edge of a bathroom mirror you will see that the picture is at the back of the glass, not the front. Or if you have a dirty mark or dust on the mirror and you look at an angle you should be able to see that reflect too. If you have a really nice Mum she might let you draw on a mirror with a water-based texta and you will be able to see the reflection of your drawing at the back.

A mirror has three parts -

• the front glass to protect it,
• a really thin layer of silver to reflect,
• a dark layer or backing to stop light coming through from the back.

All metals are shiny and reflect, but most metals react with air very quickly and lose their shine. We use silver in mirrors because it starts off very shiny and it takes much longer to react than most metals. Then to help it even more we use the glass and backing to protect it.

The glass is also good because it is so smooth and flat and lets us use a very thin layer of silver. Silver is expensive and we don’t want to use much, and the flatter it is then the better the reflection it will give us. Try looking at yourself in two spoons – one that is new and has no scratches, one that’s old. You will see a much better picture in the new, smooth spoon. Then try to clean or polish the old spoon and see what happens. Or try the same thing with smooth alfoil, then scrunch it up into a ball and look when it’s all wrinkled.

An activity

Can you do a self-portrait using a mirror? If you have a real mirror from a craft shop you could do a really good one, especially using something like oil pastels or glass paints. But you can have fun with a simple homemade one as well.

• Get some very smooth alfoil and spread it over a book or board so it is supported.
• Either use an easel or look down on it and you’ll see yourself. Make sure there are no lights directly shining on the foil or they’ll drown out your reflection.
• Carefully draw over your reflection to get a picture of you. You might need to experiment to find what will work on the shiny surface, I’ve used textas successfully but you have to be careful to let them dry or they will smudge.

Self-portrait of big girl, little girl just had fun drawing on something different!

We have all sorts of rocks and dirt around my house. I know this partly from what ends up in my bag or pockets on walks, partly from what I pour out of shoes, and partly from what I scrub off the bath. They’re a decidedly recurring fact of life, so I decided to do something with them.

Not quite as pretty as jars with coloured sand and the girls flatly rejected my suggestion of tilting them to get layers at different angles. They wanted them nice and flat thank you very much. But simple and fun, with lots of little jobs different people could handle.

First we collected some rocks and sand to use.

River sand, rocks, fine dust and old potting mix.

Flotation is the easiest way to clean up the rocks, with the girls pointing out that all the leaves and grass float and the rocks sink.

Little girl scooped them out (after adding some red food colouring to the mix),

while the big girl sifted the rocks and lumps out of the fine dust.

Then they chose which order to pour the layers into their jars.

Done.

Not quite the way I imagined them, but the girls are very proud of them and have displayed them inside. Definitely worth it for an activity that can be split to give kids their own jobs and be made simple for little ones. See what rocks and sand you have around your house.