.
Experimental Design: Plan an experiment in which you can test your hypothesis.
Test Your Hypothesis by Doing an Experiment: Your experiment tests whether your
hypothesis is true or false. It is important for your experiment to be a fair test.
Hypothesis: The hypothesis is an "educated guess," formed as a statement, that you
propose to be the answer to the research question. An educated guess is based on some
prior knowledge
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Variables: You conduct a fair test by making sure that you change only one
variable at a time while keeping all other conditions and variables the same. The
experiment will contain an element or elements that do not change (called
controlled variables or dependent variables) and elements that will change (called
manipulated variables or independent variables).
Control: The control is a particular sample that is treated the same as all the rest of the
samples except that it is not exposed to manipulated variables. In many experiments it is
important to perform a trial with the independent variable at a special setting for
comparison with the other trials. This trial is referred to as a control group. The control
group consists of all those trials where you leave the independent variable in its natural
state. In our example, it would be important to run some trials in which the plants get no
fertilizer at all. These trials with no fertilizer provide a basis for comparison, and would
insure that any changes you see when you add fertilizer are in fact caused by the fertilizer
and not something else.
Materials: List all supplies and equipment.
Example:
250 ml. glass beaker
1 straw
150 ml. Lime Water
10 g. Baking Soda
Source: http://www.sciencebuddies.org/science-fairprojects/project_scientific_method.shtml
Procedure: The procedure is a somewhat detailed, step - by - step description of how
you conducted your experiment. Example: "After 1 minute, I stirred in the baking
soda and timed the reaction to be 45 seconds." Key Elements of the Experimental
Procedure

Description and size of all experimental and control groups, as applicable
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
LOGICAL STEPS: A step-by-step list of everything you must do to perform
your experiment. Think about all the steps that you will need to go through to
complete your experiment, and record exactly what will need to be done in each
step.

IV:CV:The experimental procedure must tell how you will change your one and
only independent variable and how you will measure that change

DV:The experimental procedure must explain how you will measure the resulting
change in the dependent variable or variables

CV and Controls:If applicable, the experimental procedure should explain how
the controlled variables will be maintained at a constant value
Repeated Trials: This is done to verify data or results. The experimental procedure
should specify how many times you intend to repeat your experiment, so that you can
verify that your results are reproducible. You should also repeat your experiments several
times to make sure that the first results weren't just an accident. Purpose of Trials is to
verify data: Every good experiment also compares different groups of trials with each
other. Such a comparison helps insure that the changes you see when you change the
independent variable are in fact caused by the independent variable. There are two types
of trial groups: experimental groups and control groups.
The experimental group consists of the trials where you change the independent
variable. For example, if your question asks whether fertilizer makes a plant grow bigger,
then the experimental group consists of all trials in which the plants receive fertilizer.

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A good experimental procedure enables someone else to duplicate your
experiment exactly!
Observation: When you interact with your experiment, you are using your senses
to observe. Does it have a smell, make a noise have color, etc.?

Collect Data: As you observe your experiment, you will need to record the
progress of your experiment. Data can be whatever you observe about your
experiment that may or may not change during the time of the experimentation.
Examples of data are values in pH, temperature, a measurement of growth, color,
distance, etc.

Journal: All scientists keep a record of their observations in some form of a
journal. The journal will begin with the date and time the experimentor collects
the data. Sometimes data will include environmental values such as humidity,
temperature, etc. Entries must be written clearly and with detail of description so
that another scientist can read the journal, simulate the conditions of the
experiment, and repeat the experiment exactly.
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
Data: The data are the values written down as the experiment progresses.
Examples of data entry on
measuring plant growth:
11/22/04 Control Plant 7.8 mm
11/15/04 Control Plant 7.4 mm
Test Plant
15.9 mm
Test Plant
16.2 mm
Test Plant
23.2 mm
Test Plant
24.9 mm

Charts & Graphs: When at all possible, illustrations of data are advisable. They
create a professional appearance and convey a great deal of information.
Examples include: Bar Graph, Pie Chart, X & Y axis Graph, Histogram, etc.
. Analyze Your Data and Draw a Conclusion: Once your experiment is complete, you
collect your measurements and analyze them to see if your hypothesis is true or false.
Scientists often find that their hypothesis was false, and in such cases they will construct
a new hypothesis starting the entire process of the scientific method over again. Even if
they find that their hypothesis was true, they may want to test it again in a new way.
Results: The results is usually in the form of a statement that explains or interprets the
data. You do not go into any detail or explanations here. You simply say in words what
your data is telling you. Example: "Test Plant 3 showed little difference in growth rate as
compared to the Control Plant."
Conclusion: The conclusion is a summary of the research and the results of the
experiment. This is where you answer your research question. You make a statement of
whether your data supported your hypothesis or not. You may have data that supported
part of your hypothesis and not another part. You may also have data that did not support
your hypothesis at all. In this case, you may explain why the results were different.
Application: The application is how the information or knowledge gained in the
experiment can be used. It is not often included in science fair projects.
Resources: One of the most important things for a student to do is recognize the people
and resources used in developing and conducting the project. Name the people who
offered knowledge or helped, and list the web sites, retail stores, magazines, books,
computer programs, etc. that were used as sources of information or supplies.
Communicate Your Results: To complete your science fair project you will
communicate your results to others in a final report and/or a display board. Professional
scientists do almost exactly the same thing by publishing their final report in a scientific
journal or by presenting their results on a poster at a scientific meeting.
Source: http://sciencefairproject.virtualave.net/scientific_method.htm
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