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How Much Bigger Is It?
If you have 2 pieces of lined paper, a pair of scissors, and a pencil, you can can figure out the power of your hand lens. First, trace around the larger lens on one piece of paper. You'll need to finish the circle yourself because of the handle. Cut out the circle so you have a piece of paper with a hole the size of the lens in it.
Now use the larger lens and look at the other piece of lined paper. Bring the lines into focus so that they're as big as they can be but still clear. Count the number of spaces between the lines that you see. Remember how far off the paper you had to hold the lens. Now hold the paper with the hole in it in exactly the same place as you held the lens. Count the number of spaces between the lines that you can see now. Divide the second number by the first number (number of lines without the lens divided by the number of lines with the lens) and you'll get the magnification of that lens. Try the same thing with the smaller lens.

Magic Water
You can use what you learned about bending light to do a magic trick! You'll need a bowl with a flat bottom or cake pan, a penny, water, and a helper. Put the penny in the bowl about half way between the edge and the middle of the bowl. Start with the bowl near you and push it away until you can't see the penny any more. Now have your helper slowly pour water into the bowl. Ta-daa! The penny comes into view.

This happens because the water bends the light. Every liquid bends light, some more than others. Here's another way to show how liquids bend light. You'll need a tall, clear class, a straw, a spoon, water, cooking oil, and, if you have it, rubbing alcohol. Pour water into the glass so it's about 1/3 full. Put in the straw. Now you need to gently pour the oil on top of the water. The best way to do this is to hold the spoon above the water and pour the oil onto the spoon. Fill the glass until it's about 2/3 full. If you have rubbing alcohol, pour it onto the spoon so it makes a layer above the water. Now look at the straw. Because each of the liquids bends light differently, the straw looks like it's not straight.

Why did the rubbing alcohol level disappear when I (or my little brother or sister) stirred the layers? As long as there is an oil level between the water and the alcohol, they won't mix. When you stir the mixture, the water and rubbing alcohol mix and become one layer. The oil doesn't mix with the water/alcohol solution and will separate back into a distinct layer after you stop stirring.