The Scientific Method Science is a methodical approach to learning about the world around us .
Steps of the scientific method
S TATE THE PROBLEM
C ONDUCT RESEARCH
M AKE OBSERVATIONS & RECORD
E XPRESS CONCLUSIONS
The Scientific method is a SCHEME for doing science
Steps of the Scientific Method
Identify the p roblem , question , or a unique observation .
R esearch the problem.
Form a question and from there create a h ypothesis & make a prediction .
Test the hypothesis – e xperiment .
O bserve and record your results – analysis .
Arrive at a c onclusion or make a general rule – inductive or deductive.
The P roblem is a scientific question to be solved. It is normally based on a problem that is:
Observed- using your senses and prior knowledge
Researched- reviewing previous studies.
“ Why do recipes tell you to add salt to boiling water ?”
Can be answered in a statement….. (usually an “if…then” statement is used)
“ If salt causes water to boil at a higher temperature, then it will cook
the food faster .”
Should be limited in it’s scope…..
“ We’re only researching the affects of salt . ”
Can be solved experimentally……
“ Observe the affects as salt is added to water that is at boiling
temperatures – under controlled conditions.
Research is the process of collecting information from your own experiences, knowledgeable sources, and data from exploratory experiments to help you understand the topic .
Do use many references from printed
sources— books, journals, magazines, and
newspapers—as well as electronic sources—
computer software and online services .
Do gather information from professionals—instructors, librarians,
and scientists, such as physicians and veterinarians .
A hypothesis is an idea about the solution to a problem, based on knowledge and research – an educated guess .
“ I think salt changes how the water affects the food. ”
Experimenting will be designed to test the hypothesis .
Do state facts from past experiences or observations on which
you base your hypothesis .
Do write down your hypothesis before beginning the project
experimentation. (Generally write the hypothesis in an “if… then statement).
“ If salt is added to boiling water then it will cause the food to cook faster”
Don't change your hypothesis even if experimentation does not
support it - that’s science! If time permits, repeat or redesign the
experiment to confirm your results.
“ TESTING ” the Hypothesis
Know your “ variables ”
Independent (manipulated) variable: is the variable you purposely
manipulate ( change ). Ex . Adding salt
Dependent (responding) variable: is the variable that changes in
response to the independent variable – water temp .
Controlled (constants) variables: are variables that are not changed .
Ex . Amount of water used.
Control Group: A group that is tested in which the independent variable is not applied. It is used as the standard by which the test results can be compared (Exp: Boiling the water without the salt added)
Does and Don’ts of Experimentation:
Do have only one independent variable during an experiment. All others must be controlled variables
Do repeat the experiment to verify your results.
Do have a control group.
Do have more than one control, with each being identical.
Do organize data.
Observe and Record
Organize data- charts; graphs; tables; etc
Analyze the data
Pay attention to detail
Interpretation and evaluation of results
Write the results in a clear and concise
manner so others can understand them
After recording the results of the experimentation, you need a s ummary of the results and a statement of how the results relate to the hypothesis . Remember :
* If your results do not support your hypothesis (refutes) :
DON'T leave out experimental results that do not support your hypothesis.
DON'T change your hypothesis.
DO give possible reasons for the difference between your hypothesis and the experimental results.
DO give ways that you can experiment further to find a solution .
* If your results support your hypothesis: Reward yourself!
When writing a conclusion make sure to include the following:
Statements on how the results of the experiment related to your hypothesis (whether it was supported or refuted)
Explanations as to why the experimental results were achieved
Other hypotheses that can be made based on the experimental results
Any experimental flaws in your experiment
Theory vs. Law
Theory - an explanation of things or events based on many observations and investigations
Law - Statement about what happens in nature that seems to be true at all times.