# The Scientific Method

Updated on January 2, 2015

Whether you realize it or not, we are all scientists every day! A scientist makes observations using the five senses, makes a guess or prediction as to what will follow based on those observations, and then conducts experiments that will prove or disprove that prediction. Analyzing the results helps us learn new things about our world, ourselves, people, and the environment, and we then go on to make new predictions based on our newfound knowledge.

First, you make an observation. Pay attention to something in your surroundings and collect sensory data. You could observe your dog eating, your parents cooking, the birds outside in the tree, your squeaky door… Anything!

Once you have a good question that you think you can answer with a test, you form a hypothesis. Your hypothesis is basically a guess. With the information you’ve gathered through your observations, provide a possible answer to your question. Your hypothesis should reflect whether or not, you think, something will change when you move onto the next step of experimentation. What does that mean? Well, if you think your dog prefers Purina, you would predict that he would eat less if you changed his food to Pedigree. The change is in how much your dog eats.

Now you can conduct the experiment in which you hope to observe a change. You are testing your hypothesis. What if your dog eats the same amount of Pedigree as he did Purina? What if he eats more? The first is a null result- meaning there was no change, and the second is a positive result. However, you were looking for a negative result in your hypothesis, so through your experiment you have proven your hypothesis wrong. What now?

Before we draw any conclusions, we need to analyze the data and information we’ve gathered through our experiment. Most importantly, it is time to start asking even more questions based on our new observations. What if there was something you didn’t consider that may have affected your results? Did your dog go for a walk before eating the Purina but not before eating the Pedigree? Was he served the same amount of each? Were they both the same flavor? With these new questions, we can form new hypotheses and formulate better experiments that will produce even greater results. Only when we are sure of our answers do we reach the final step of conclusion, and even then we may go back and continue to experiment with new thoughts and ideas.

Professional scientists will research experiments that others may have done on the same topic, and will conduct their own experiments to see if their results are the same. Ideas or hypotheses that have been tested over and over again and lead to the same conclusions are considered scientific facts. A theory is then developed to explain these facts. Theories give us a strong scientific foundation, but should even one experiment prove a theory wrong, we would have to start anew with the development of a new theory.

## Experiment Ideas for Young Children to Practice the Scientific Method

Does air weigh anything? Form a hypothesis after reading below.

Balance a scale with an un-inflated balloon on each side. Inflate one of the balloons and return it to the scale. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Try filling the balloon with water or helium.)

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Will an egg sink or float? Form a hypothesis after reading below.

Start with a raw egg. Fill one cup with salt water, and another with regular water. Place the raw egg in each cup and observe. What happens? What are your conclusions?

How could you improve your experiment? (Hint: What happens when the egg is hard-boiled? When fill the cup half-way with salt water, and then add regular water?)

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What conducts electricity? Form a hypothesis after reading below.

You will need a “battery kit” that can be found in craft stores, and a light bulb. Connect the light bulb and make sure it works by touching the wire ends together to close the electric circuit. Then, test different things to see if they conduct electricity by touching the wires to either end.

Suggestions: Yourself (hold the wire ends in each hand), water, salt water, a coin, a pickle. What happens? What are your conclusions?

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How far will it fly? Form a hypothesis after reading below.

Make two paper airplanes, one with broad wings and one with thin wings. Throw each of them and measure the distance they travel. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Try throwing the planes from different angles- stand on a chair or lay on the ground.)

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Can salsa clean a penny? Form a hypothesis after reading below.

Place two dirty pennies on a plate and cover them in salsa. Leave them sitting for a few minutes, then rinse them off and compare the side that touched the salsa to the side that didn’t. What happens? What are your conclusions?

How could you improve your experiment? (Hint: The main ingredients of salsa are salt, vinegar, and tomato paste. Try testing each one by itself and in different combinations.)

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What is water surface tension and how does it work? Form a hypothesis after reading below. (This is two experiments)

Take an empty soda bottle and poke a hole near the bottom with a nail or push pin. Cover the hole with your finger, fill the bottle with water, screw on the lid, and then remove your finger. What happens? Unscrew the lid and observe. What happens now?

Take two glasses, one filled with water and one empty. Take a long flat stick (straw, piece of silverware, etc), place it on top of the full glass so that it sticks outward, and then pour the full glass into the empty glass. What happens? What are your conclusions?

How could you improve your experiment? (Hint: What happens if you place a piece of paper on top of a full glass and flip it over?)

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How does a compass work? Form a hypothesis after reading below.

Magnetize a sewing needle by rubbing one end on the “north” side of a magnet about 50 times. Float the needle in a bowl of water and observe. This works best if the needle is also taped to a piece of wax paper to help prevent sinking. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Try rubbing your needle on the south side of the magnet, or rubbing one side on north and the other side on south.)

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What do plants need to grow? Form a hypothesis after reading below.

Take some beans and place them in four different bags with paper towels. Squirt water into two of the bags before sealing. Place one watered and one unwatered bag by the window, and place one watered and one unwatered bag in a dark closet. Leave them for about a week. Bring them together and record your observations. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Try different soil combinations, different amounts of water, and/or different amounts of sunlight.)

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How does sunblock work? Form a hypothesis after reading below.

Paint a picture on a colored piece of construction paper with sunblock. Place the picture in a sunny location and leave it there for at least a day. Bring the pictures inside. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Does having a different level of SPF make a difference?)

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What can static electricity move?

Rub a balloon on your head to charge it and see what happens to your hair. Try using this charged balloon to push objects across the floor, like a ping pong ball or a can. Now charge a comb by brushing it rapidly through your hair. Turn on the faucet so that it is running a very slow stream of water and slowly move the comb toward the water. What happens? What are your conclusions?

How could you improve your experiment? (Hint: Try holding a statically charged object up to a fluorescent tube light.)

## Definitions

Scientist-

A person who make observations about the physical world, gathers evidence and information, and then learns from those observations through a series of tests or experiments

Observation-

The action or process of observing something or someone carefully or in order to gain information- using the senses of sight, touch, hearing, smell, and taste

Question-

An idea or inquiry out of curiosity that may lead to the gathering of information

Hypothesis-

A supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation

Change-

The act or instance of making or becoming different; change can be physical, chemical, behavioral, etc.

Experiment-

A scientific procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact

Null-

Nothing; no change; a hypothesis and/or result in which no difference occurs between the original state and that after the experiment

Positive-

A change involving an increase of one form or another

Negative-

A change involving a decrease of one form or another

Conclusions-

Analyze-

To examine methodically by separating into parts and studying their interrelations; Comparing and evaluating your data in order to reach a conclusion

Research-

The systematic investigation into and study of materials and sources in order to establish facts and reach new conclusions

Fact-

A thing that is indisputably the case

Theory-

A supposition or a system of ideas intended to explain something and on which the practice of an activity is based

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