Scientific Method

Steps in the Scientific Method Observe & Ask Questions Observe & Ask Questions Form a Hypothesis Form a Hypothesis Plan an Experiment Plan an Experiment Conduct the Experiment Conduct the Experiment Draw Conclusion Draw Conclusion Present Results Present Results *On Friday People Call Dominoes Pizza

Observe & Ask ??s Gathered through your senses Gathered through your senses A scientist notices something in their natural world A scientist notices something in their natural world

Observe & Ask ??s An example of an observation might be noticing that many salamanders near a pond have curved, not straight, tails. An example of an observation might be noticing that many salamanders near a pond have curved, not straight, tails. Question? Why are their tails different? Question? Why are their tails different?

Form a Hypothesis A suggested solution to the problem A suggested solution to the problem Must be testable Must be testable Sometimes written as If…Then… statements Sometimes written as If…Then… statements Predicts an outcome Predicts an outcome

Form a Hypothesis An example of a hypothesis might be that the salamanders have curved tails due to a pollutant in the moist soil where they live. An example of a hypothesis might be that the salamanders have curved tails due to a pollutant in the moist soil where they live.

Plan an Experiment A procedure to test the hypothesis. A procedure to test the hypothesis.

Plan an Experiment Variable – factor in the experiment that is being tested Variable – factor in the experiment that is being tested

Plan an Experiment A good or “valid” experiment will only have ONE variable! A good or “valid” experiment will only have ONE variable!

Scientific Experiments Follow Rules An experimenter changes one factor and observes or measures what happens.

Conduct the Experiment Do the experiment the way you planned.

Draw Conclusions The answer to the hypothesis based on the data obtained from the experiment

Present Results Tell others about your findings. Explain how your experiment turned out and anything new you discovered.

Valid Experiments are conducted over and over again! In order to verify the results, experiments must be retested.