Link to Producers

Link to Primary Consumers

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Take the next step up the foodchain to take a look at predators.

This time our experiment is one that winds up in lots of science fair projects. Does color have an impact on how things absorb heat?

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Don't let the title fool you. This experiment does not involve any explosions. Instead, we are going to explore the science of resonance. Resonance involves putting in small amounts of energy, at just the right time, to get more effect. A good example is pushing a swing. Each push causes the person in the swing to go higher. We will lift a phone book high into the air by blowing on it.

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Link to Primary Consumers

Link to Secondary Consumers

Explore the role of producers, organisms that specialize in capturing energy, converting it into useable forms, and storing it.

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Learn to construct a 25,000 volt Leyden Jar from materials found around the house. This dramatic, yet safe, demonstration is a great way to learn about electrostatics, charges, and circuits.

This project has science fair potential.

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A musical exploration of sound and vibration.

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A flame that seems to move in the wrong direction. Why?

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Link to Making a Cloud Chamber Video

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What does it mean when we say that something is radioactive?

Science Fair Thoughts

What household substances are radioactive? How long is a half-life? Which kinds of atomic particles can you detect with a cloud chamber?

What does it take for something to burn?

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Thoughts on Trees

This is another post that comes from the Science Photo of the Day. It worked well there, but has great potential for a full blown Experiment of the Week activity. To try this, you will need:

- a plant or some seeds
- a pot to grow the plant in
- potting soil
- a scale to weigh the plant, pot, and soil

We will explore how plants grow, by growing a potted plant. You can use a plant from your local garden shop, or you can plant seeds from your favorite plant.

Start by weighing the pot. Then put the soil into the pot and weigh it again. Finally, add the plant or seeds to the pot, and weigh it one more time. This will let us calculate the weight of the plant (weight of everything minus weight of the pot and soil) as well as the weight of the soil (weight of the pot and soil minus weight of the pot.) Be sure to write everything down, as we will need that information later.

Then all you have to do is get the plant to grow. Give it water, and plenty of sunlight, but don't add anything else. As the plant gets larger, weigh it again. You should find that it has gained weight, even though you have not added any soil. Where did that extra weight come from?

To find out, start by looking at trees. Don't just think about trees. Look out the window, or even better, go outside. Notice how big trees are. Wrap your arms around the trunk, and get a feel for how strong it is. Think about how much wood is in that tree. Think about all the leaves that it produces and drops on your lawn. Think about how heavy those leaves are when you rake them up and haul them away.

Where does all that stuff come from? Your first thought is probably that it comes from the soil. After all, our bodies build up their mass from the food that we eat, and plants eat by taking in nutrients from their roots, don't they? Think about that for a minute. Look at the ground around the tree. If the tree had removed enough matter from the soil to build its trunk and branches, there would be a huge hole around the tree. Then think about your potted plant. It gained weight, which did not come from the soil in the pot.

Plants are not like us. They don't take in food. Instead, they make their own food, through the process of photosynthesis. To do that, they need energy, which they get from sunlight. They also need hydrogen, oxygen, and carbon as the chemical building blocks to make their food. They get those chemicals from water (hydrogen and oxygen) and carbon dioxide (carbon and oxygen.) During photosynthesis, these chemicals are recombined to form sugar. That sugar can be used as it is to provide energy for the plant, or it can be converted into other substances such as starch and cellulose, which make up the trunk, branches, roots, and leaves of the tree. Almost the entire tree is made of the chemicals from rain water and carbon dioxide from the air, and the same is true for your potted plant. It is also true for apples, peaches, strawberries, etc. When you think about it, even chocolate is made from plants. The sugar from plants, and so is the cocoa. That means that chocolate is mostly made up of sunlight, water, and air! Sounds yummy to me!

Have a wonder-filled week.

Why Paper Burns

This week's experiment is a result of a question sent to me by a list member. It is one of those questions that seems so simple until you try to explain it. To get started, you will need:

- a strip of paper about 4 inches long
- a pan of water
- a match or lighter

Warning: This experiment uses fire. Never work with fire unless there is an adult with you. That gives you someone to blame if something goes wrong.

Hold the paper over the water. Use the match to light the end of the paper. Watch it burn for a second, noticing the light and heat coming from the flame. Then drop it into the water to put it out. Why does the paper produce that light and heat? Why does it burn?

The key to the answer is energy. There are many kinds of energy, such as heat, light, electrical, nuclear (pronounced nu-cle-ar, not nuk-u-ler), etc. The laws of thermodynamics tell us that we cannot make energy, and we cannot get rid of it. We can only change it from one form to another.

The light and heat energy of the burning paper had to come from somewhere. It came from the paper. Now, where did the paper come from? Paper is made from wood. And where does wood come from? Trees.

Trees are plants. Where do plants get their energy? From the sun. Plants use a process called photosynthesis to trap energy from the sun. They combine water, carbon (The black stuff left behind when you burned the paper.) and the energy from sunlight to make sugar.

This sugar is then used to make other chemicals. By connecting many sugar molecules together into a long chain, the plant produces cellulose. That is what wood is made of. A piece of wood is really just a big chunk of sugar. The chemical structure has been changed, so it does not taste sweet, but it still contains the energy that was put into the sugar. When you burn a piece of wood, the heat causes the molecules to come apart, releasing the trapped energy, as the light and heat of the flame.

If you take the piece of wood and mash it into a pulp, then you can process it into a sheet of paper. Although it looks different, it is still made of cellulose, so it still contains the trapped energy. Burning the paper releases the energy, just as it does when you burn a piece of wood.

Now, look at another piece of paper. You can't see the energy, but it is there, hidden inside. Science is hidden all around you, if you just take the time to wonder about things.

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Pendulum Perils

Are you brave enough to try this?

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Ice Cream Spoons

Why do some spoons work better than others?

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Action and Reaction

If you push, things push back!

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Static Glow

Lighting a light bulb with a balloon is not nearly as difficult as you might think.