Scientific Method

Independent/ Manipulated variable• This is the thing that you will change or manipulate, the

thing you are testing.

Dependent/ Responding variable• This is the thing you measure or observe, the results of

the experiment.• You expect the dependent variable to be affected by

the independent variable

Control variable• Any variable that you keep the same in order to

allow for a fair test.

Scientific Method • A process for experimentation that is used to explore observations and answer questions.

Scientific MethodMain Ideas Details

Steps of the Scientific Method(Simplified)

1. Ask a question.2. Do background research.3. Construct a hypothesis.4. Test hypothesis with an experiment.5. Analyze data and draw a conclusion.6. Communicate results.

Ask a Question

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Ask a question about something that you observe: How, What, When, Who, Which, Why, or Where?

Research Research to help you find the best way to do things and to learn from past mistakes.

Hypothesis

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The experiment tests whether your hypothesis is true or false. Repeat the experiment.

Experiment

A hypothesis is an assumption about how things work: "If _____[I do this] _____, then _____[this]_____ will happen.”

Analyze Data

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Scientists publish their final report in a scientific journal or by presenting their results at a scientific meeting.

Communicate Results

Analyze the data to see if your hypothesis is true or false. Scientists often find that their hypothesis was false. They construct a new hypothesis, starting the entire process of the scientific method over again.

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Experiments – Variables

• Variables are things (or factors) that have an effect on your experiment. There are three kinds of variables.

• Independent• Dependent• Control

Cheaper hamburger meat contains more grease than higher priced hamburger meat."

Sample Hypothesis

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Independent variable

• Also known as the INPUT (manipulated) variable. This is the thing that you change or manipulate, the thing you test.

• The price of the hamburger meat is the independent variable. It is changed by testing different meat of different prices.

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Dependent variable

• Also known as the OUTPUT (response) variable.

• This is the thing you measure or observe, the results of the experiment.

• The dependent variable is affected by the independent variable

• The amount of grease in the hamburger is the dependent variable, it changes depending on the price of the hamburger meat.

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Control variable • Any variable that you keep the same in order to allow for a fair test.

In our example • The temperature and humidity of the room where the experiment is conducted, must be kept the same for every experiment.

• the type of meat should be kept constant (for example, there could be a big difference in the level of greasiness between beef and chicken).

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In our example •The meat should be purchased from the same grocer. Prices and quality of meat vary across grocers.

•All of these variables are called control variables.

Scientific MethodMain Ideas Details

What other Control Variables would we need to include?

•Use your brain and think. •Raise you hand to answer.•Write down what your classmates come up with for additional Control Variables.

Scientific Method

Main Ideas Details

Summary – Write a 3 to 5 sentence summary.

Independent/ Manipulated variable• This is the thing that you will change or manipulate, the

thing you are testing.

Dependent/ Responding variable• This is the thing you measure or observe, the results of

the experiment.• You expect the dependent variable to be affected by

the independent variable

Control variable• Any variable(s) that you keep the same in order to

allow for a fair test.