Prickles, Lizards, Ogres, Collectible Cards and Calculus

[This is a back-issue of one of this site’s newsletters]

The other day, after a walk, I found a double-gee seed stuck in my shoe. A nasty little weed. Lucky I was wearing shoes!

It reminded me of a story of how kids used to sell these seeds to visiting sailors, claiming they were the eggs of a lizard called the Thorny Dragon. This lizard is quite amazing. One of its tricks is that water condensing on its body makes its way via capillary action to the mouth – a useful trick for a desert reptile!

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[DMMGFK #72] April Fools Date Calculator

[This is a back issue of one of this site’s newsletters]

 

It’s been a long tiome since I uploaded a new game to Dr Mike’s Math Games for Kids, but here’s one at last… an April Fool’s Date Calculator.

Just as for Easter, there’s a formula that can calculate the date of April Fool’s Day in any year. I’ve taken that complicated formula and distilled it into a worksheet that kids can use.

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What happens to water as it cools?

This experiment would have been far, far better if I’d had a thermometer.

My son was doing some science homework, and seemed a bit confused about what would happen to hot and cold water if left on the table.

Now whenever possible, if your child expresses confusion about a science topic, don’t just explain, do an experiment. Most science for young kids is informal enough and practical enough that there’ll be some way to do the experiment around the house.

In this case, it was simple. I filled one cup with water from the kettle, another with water and ice. I asked my son to label each cup, and write down his predictions about what would happen in the end. You can see the setup below:

The Experimental Setup
The Experimental Setup

If we had had a thermometer, I would have asked him to measure the temperature of each cup at various time intervals, say immediately, after 5 minutes, 10 minutes, 20 minutes and an hour. Then he would have been able to see that both cups reach the ambient temperature of the air around them. As it was, his “thermometer” was to dip his finger in the cups. Too subjective, alas. I’ll have to get a thermometer and try again one day.

Using an elastic band to fling cars away FOR SCIENCE!

[This is a back-issue of one of this site’s newsletters]

One of my 7 year old son’s science books suggested this experiment.

I got a block of wood, and hammered two nails onto it. He strung an elastic band between them, so he could use the block as a little projectile launcher.

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