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Careful observation is a very important part of science. Ornithologists learn to identify birds from a quick glimpse as they fly through the trees. Meteorologists learn to read the clouds in much the same way that most people read books. Geologists learn to look at a hillside covered with gravel, and spot the one piece that happens to be a fragment of dinosaur bone. Part of this is learning what to look for, but part is also training your eyes to really see all the details that are there. To give this a try yourself, you will need:

• several chocolate chip, oatmeal raisin, or other cookies. Homemade are tastier, but you can use store bought cookies too.
• paper to draw on
• pen, pencil, crayons, or something else to draw with.
• a ruler

Pick two cookies at random. Eat one. Place the other on the table in front of you. Look at the cookie. I mean, REALLY look at it. Imagine that you are going to have to look at a pile of similar cookies, and know this one well enough to pick it out of the pile.

Draw a picture of your cookie, being sure to note any identifying marks. Maybe one of the chocolate chips has a crack in it, or there may be two raisins at the edge that almost touch each other. Don't worry if your drawing is not perfect. You are recording your observations, so as long as it shows the things that make your cookie special, it is a wonderful drawing.

Measure your cookie, noting on your drawing any measurements that could help identify it. Maybe one side is thicker than the other, or it may be 1/4 inch wider at the point where the two raisins almost touch. Again, pretend that you need to record your cookie well enough to pick it out of a lineup of other cookies.

Once that is done, put your cookie in with all the others. Close your eyes and have someone mix them well. If you are doing this on your own, close your eyes and shuffle them well. Then open your eyes, and find your cookie. Check it against your drawing and measurements to be sure that it is your cookie.

How well did you do? If you want to make it a bit more challenging, try using cookies that are manufactured to be very similar. Oreos work very well for this. They all seem to look alike, but if you look carefully, you can spot irregularities in the filling, top cookies that are not exactly aligned with the bottom, and other small differences.

Want to make it a bit more challenging? Ask someone else to look at your drawing and notes, to see if they can identify your cookie. This takes more practice and skill, but it is a skill well worth learning.

Once you are done, you will have a pile of cookies that have been handled. That means that you can't put them back in the package, so dispose of them properly. I like mine dipped in either milk or hot tea.

The more you practice observation, the more you will see in the world around you. You can do this activity with other objects, such as pennies, rocks, leaves, or sticks, but in that case, skip the step where you eat one.

Printer Friendly File - Printable Graph Paper

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This is something that comes up quite frequently in discussions between scientists and the general public. How much proof does it take for a theory to graduate to being a law?

Theory

Law

Because the words theory and law have such different meanings in the language of science, it is often a difficult question to answer, so instead, I'll start by giving you a few similar questions to answer.

1. How perfectly do you have to build a house so that it will become a single brick?
2. How well do you have to write to change an entire dictionary into a single word?
3. What would you have to do to change an entire symphony into a single note?

If you are thinking that those questions don't make much sense, then you are feeling very much like a scientist who has been asked "How much proof does it take for a theory to graduate to being a law?" A house is made up of many bricks, boards, nails, windows, doors, concrete, etc. A dictionary is made up of thousands of different words, and a symphony can easily have thousands of notes that all fit together in just the right way to produce pleasing music. In the same way, theories are based on a variety of scientific laws, facts, testing, and other evidence, all fit together in a way that offers an explanation of how some part of the universe works.

Ohm's Law

In science, laws are simple facts and formulas that are so basic that they apply universally. For example, Ohm's Law has the formula I=V/R, which tells us that in an electrical circuit, the amperage is equal to the voltage divided by the resistance. That is it. All of it. It is an important law if you are working with electricity because it applies to any electrical circuit, but it tells us nothing about what amperage is, why it equals voltage divided by resistance, or what we can do with the information. It is simply one of the "notes" in the symphony of Electromagnetic Theory, which explains why light bulbs light, why electric heaters heat, and why computers compute.

So just as houses don't become bricks, theories don't become laws. Both are important, but they tell us very different things.

But what if a theory turns out to be wrong? What if it has a flaw? Well, lets go back to the earlier questions. What if you build a house, and then realize that there is a room with no door, no way to get in or out. Clearly, something is wrong. Do you walk away, and start all over from scratch? Or do you look to see if there is a way to install a door to make the room useable? Or maybe you decide that the room is not necessary, and remove that part of the building. The same is true for scientific theories. Finding one flaw in the theory of gravity would probably not send everyone back to construct an entirely new theory. Instead, scientists would examine the new evidence, and see if there was a way to adjust the theory so that the new evidence fit. That happens quite frequently. As we learn more and more about the universe, we expand and refine our theories about how the universe works.

Occasionally discoveries are made that are so profound that they do require that we discard the old theory, and start from scratch to develop a new one that fits the new evidence as well as the old. Then the testing begins, with everyone looking for evidence that the new theory is wrong. Wrong? Isn't it mean to try and prove that it is wrong? No. It is the way of science. In the words of a famous scientist:

Even after all those years, scientists are still performing tests to see if there are flaws in Einstein's Theories of General and Special Relativity. Neither has been shown to be wrong, so they are still accepted and highly respected scientific theories.

The same is true for new explanations of how and why things work. After a great deal of testing, and with enough solid evidence, often with much modification as more evidence is gathered, a new explanation may eventually be accepted for the exalted title of Theory.

As we will see over and over, there are many words that mean one thing in everyday language, and something very different in the language of science. Words such as mineral, rock, force, or radiation have very specific meanings for scientists, usually quite different from the definitions used in daily life. The words "hypothesis", "law", and "theory" may well be the three most misunderstood words in science, so lets take a look at them, to see what they really mean.

• What is a Hypothesis?
• Is Gravity a Law or a Theory?
• When Does a Theory Become a Law?

As you learn the process of science, wouldn't it be great to be able to watch expert scientists at work? By watching the way they approached new problems, tested ideas, and revised their views based on the evidence they collected, you could improve your understanding of how science works.

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The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!'
(I found it!) but 'That's funny ...' - Isaac Asimov

Now that we have a workable definition of science, lets use that to take the next step. What do scientists do? When you hear the word "scientist", you probably think of people in white lab coats, mixing chemicals or peering into microscopes. Some scientists do that, but science is a much broader subject.

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Why do we have to study science? What good is it? For that matter, what is it? That question, "What is science?", is a very good one, and not easy to answer. Many different definitions have been proposed by different sources. After looking through many of them, I have tried to combine and distill them into a workable definition that we can use in our study of science.

OK, so for our purposes:

As we have seen before, the easiest way to understand long definitions is to take them apart, and look at them bit by bit. Then, when we put them back together, they are easy to understand. We can look at those parts in any order, but there are some parts that make it easier to understand others, so we won't just go down the line. Instead, I suggest that you look at them in this order.

1. The Natural World
2. Observation
• Answers to Observation video
• Observations on a Cookie.
3. Objective
4. Experiment
5. Repetition and Replication
6. Gather and Organize
7. Self Correcting

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