Target: I can write a testable hypothesis.

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Target I can write a testable hypothesis.
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Steps in the Scientific Method

• Observation
• Hypothesis
• Experiment
• Data Collection
• Conclusion
• Retest

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Hypothesis

• An educated guess about how things work.
• Must be testable
• Sometimes written as IfThen statements
• Predicts an outcome

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Hypothesis

• Example If the salamanders are exposed to
  pollutants in the moist soil, then they will have
  curved tails because of DNA mutations.

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Practice Writing Hypotheses!

• Check your work with your neighbor!

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Target I can distinguish between an independent
and dependent variable.
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Experiment

• A procedure to test the hypothesis.

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Independent Variable

• The factor that is changed or manipulated

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Independent Variable

• Imagine that you wished to know whether listening
  to music would increase productivity in the
  workplace.  What is the independent variable?

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What are the independent variables of your
experiments?

• Check your answers with a DIFFERENT neighbor.

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Dependent Variables

• The factor that is measured or observed is called
  the dependent variable.
• Imagine that you wished to know whether listening
  to music would increase productivity in the
  workplace.  What is the dependent variable?

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What are the dependent variables of your
experiments?

• Check your answers with a DIFFERENT neighbor.

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Hand Check!

• Thumbs up you can distinguish between an
  independent and dependent variable
• Thumbs down still not sure

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Target I can identify a control. I can explain
the purpose of a control.
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Controlled Experiment

• Two Groups an experimental group and a control
  group
• The only difference between the groups should be
  the independent variable.

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Example
Imagine that you wished to know whether listening
to music would increase productivity in the
workplace.  Which is the control group? Which is
the experimental?
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Name the two groups for your experiments?

• Check your answers with a DIFFERENT neighbor.

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What is the Purpose of a Control Group?

• To show what would normally happen and compare it
  with what happens when you change the independent
  variable.
• Shows if the independent variable is really
  responsible for your observations.

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Explaining!

• Turn to your partner and explain the difference
  between an experimental group and a control
  group.
• Then switch.
• How did your partner do?
• What is the purpose of the control group?

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One Independent Variable per Experiment!

• Imagine that you wished to know whether listening
  to music or chewing gum would increase
  productivity in the workplace.  What is wrong
  with this experiment?

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Constants

• Also called controlled variables
• Never change in any group.
• Imagine that you wished to know whether listening
  to music would increase productivity in the
  workplace. What are some constants?
• Write the constants for 6

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One more thing it is best to make several trials
with each independent variable.Why?
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Rate Yourself on the Targets!

• 1 Get and can explain it
• 2 Kind of get it, couldnt really explain it
• 3 I have no idea what just happened
• I can write a testable hypothesis
• I can distinguish between an independent and
  dependent variable.
• I can identify a control.
• I can explain the purpose of a control.