Wednesday, 23 July 2008

Ahoy there!

As of today both the boys can now sail on their own!!!

We spent pretty much all day at the Sailing Club and the weather was perfect, beautifully calm and warm, and ideal for the kids to go out and have a try. So they did!! The boys' achievement today is fantastic, especially when I look back and realise that a few weeks ago they'd never even been in a boat!

Arriving around 11m, we met up with friends, and the kids spent some time pond-dipping (caught some quite big 'tiddlers') and paddling. They then moved indoors and we had to prise them away from the pool table and table football to get them to eat luch.

After lunch we got some Optimists out. One we left with no sail. It was tied to the jetty in the shallows for the littlies to sit in; they were chuffed to think they were being included in the 'sailing'. The others went out and we took turns. At first the kids were accompanied by adults, until they felt confident enough to go out on their own. Mostly the kids osailed as far as the first buoy: we figured that if they got into trouble it would be easier to rescue them there than if they went right across the lake! Ds1 even took dd1 out for a sail, which she loved. The water was so calm and he seemed quite competent, so I had no qualms about it. Perhaps not on a windier day, though .

So, our next sailing session is planned for early next week I think. I have grand plans for lots of projects and outdoor stuff to take place around the lake, not just sailing. Perhaps lots of reading, some science stuff, my head is already running away with the possibilities though at some point I'll face the reality that the kids might not be so keen! Ah well, even if all my plans don't come to fruition, it's exciting to think of all the things we might do there over Summer.


After thinking of doing science at the lake I was reminded of the Krampf experiments I sign up to via email (see . Robert Krampf is a geologist/scientist who gives talks and demonstrations. He is so keen to enthuse others about science, particularly kids, that he records free science videos for viewing on his website, and sends out emails with experiments to 180,00 households in more than 95 countries (apparently). The experiments are generally short, fun and fairly simple. Instructions given with a simple, but not patronising, explanation of the science behind the experiment. This one below particularly caught my eye because I remember being taught at school that this was an experiment to show how oxygen was being used up. Three A levels and a Science Degree later, I find out that the explanation I was given as a child - and have seen many times subsequently in children's science books - is totally WRONG!! See, with this home education thing, even the parents are learning all the time...

"Measuring Oxygen?
Every year, I reread Michael Faraday's Chemical History of a Candle. It is a transcript of some of his annual Christmas science lectures, and it is a wonderful example of science education at its best. It is also filled with marvelous experiments, including a version of this one.
Warning! This experiment uses fire. Be very careful and be sure an adult is around to help.
For this experiment, you will need:
- a pie pan or shallow bowl
- a candle
- a glass jar large enough to hold the lit candle
- water
Light the candle and let a few drops of melted wax fall on the middle of the pan. Place the bottom of the candle into this wax to secure it in place. Carefully add about an inch of water to the pan. Relight the candle if it has gone out, and place the jar over it. Watch carefully. After a minute or so, the candle will go out, and the water will rise up into the jar.

This shows that the candle has burned up the oxygen, and the water has risen into the jar to take its place, right? WRONG!!!!! If you watch carefully, you will see why is it wrong. When you first place the jar over the candle, air bubbles OUT of the jar. If you are slow about placing the jar over the candle, you might not notice this, but if you cover the candle in one quick motion, you will see the air bubbling out. Once the candle goes out, the water begins to rise in jar.
Now, lets think about that. If the water was rising because the oxygen was burned up, it would rise while the candle was burning and stop as soon as the flame went out. Is that what you saw? No. Then what really did happen?
As the candle burns, it is heating the air in the jar, causing it to expand. This causes the bubbles that leave the jar. The candle is burning oxygen, but the oxygen does not vanish. It combines with carbon from the burning wax to form carbon dioxide, another gas that also takes up space.
When the candle goes out, the air begins to cool, which causes it to contract. As the air gets smaller, the water rises into the jar.
It amazes me how many books of experiments get this one wrong. I guess they should read more Faraday. "


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