The Scientific Method
A science project is an investigation using the scientific
method to discover the answer to a scientific problem. Before starting your project, you will need
to understand the scientific method. The
scientific method is the ¡§tool¡¨ that scientists use to find the answers to
questions. It is the process of thinking
through the possible solutions to a problem and testing each possibility to
find the best solution. The scientific method
involves the following steps:
- Doing research
- Identify the problem (in question form)
- State the hypothesis
- Conduct an experiment
- Observe and record your data
- Draw a conclusion
Doing Research
Research is the process of collecting information from your
own experiences, knowledgeable sources, and data from exploratory experiments. Your first research is used to select a
project topic. This is called topic research. For example, you observe a black growth on
bread slices and wonder how it got there.
Because of this experience, you decide to learn more about mold growth. Your topic will be about fungal reproduction.
After you have selected a topic, you begin what is called project research. This is research to help you understand the
topic, express a problem, propose a hypothesis, and design one or more project
experiments- experiments designed to test the hypothesis. Investigate what others have already learned
about your question. The result of this
experiment and other research give you the needed information for the next step
¡V identifying the problem.
¡P
Do use as many references from printed sources ¡V
books, journals, magazines, and newspapers ¡V as well as electronic resources ¡V
computer software and online services.
¡P
Do gather information from professionals ¡V
instructors, librarians, scientists, such as physicians and veterinarians.
¡P
Do perform other exploratory experiments related
to your topic.
Identify the Problem
The problem is the scientific question that needs to be
solved. It is best expressed as an
¡§open-ended¡¦ question, which is a question that is answered with a statement,
not just yes or no.
These questions may
begin with the word how, why, or when but shouldn¡¦t begin with the word does or
is.
¡P
Do limit your problem
¡P
Do choose a problem that can be solved by
performing an experiment.
State a Hypothesis
A hypothesis is a possible answer to a scientific question,
based on knowledge and research. While
the hypothesis is a single statement, it is the key to a successful
project. All of your project research is
done with the goal of expressing a problem, proposing an answer to it (the
hypothesis), and designing project experimentation. Then all of your project experimenting will
be performed to test the hypothesis. The
hypothesis should make a claim about how two factors relate.
Here is one example of a hypothesis:
¡§I believe that bread mold does not need light for
reproduction on white bread. I base my
hypothesis on these facts: (1) organisms with chlorophyll need light to
survive. Molds do not have chlorophyll
and (2) in my exploratory experiment, bread mold grew on white bread kept in a
dark bread box.¡¨
¡P
Do state facts from past experiences or
observations on which you base your hypothesis.
¡P
Do write down your hypothesis before beginning
the project experimentation.
¡P
Don¡¦t change your hypothesis even if experimentation
does not support it. If time permits,
repeat or redesign the experiment to confirm your results.
Conduct an
Experiment
Project experimentation is the process of testing a
hypothesis. The things that have an
effect on the experiment are called variables.
There are three kinds of variables that you need to identify in your
experiment: manipulated, responding, and controlled. The manipulated
variable is the variable that you purposely manipulate (change). The responding
variable is the variable that is being observed, which changes in response
to the manipulated variable. The
variables that are not changed are called controlled
variables.
A controlled experiment is a test in which you are only
changing the manipulated variable on purpose. All other variables are held
constant.
Scientists run experiments more than once to verify that
results are constant. Each time that you
perform your experiment it is called a trial.
¡P
Do have only one manipulated variable during an
experiment?
¡P
Do repeat the experiment more than once to
verify your results?
¡P
Do have all variables set constant except for
the manipulated variable?
¡P
Do organize data?
Draw a Conclusion
The project conclusion is a summary of the results of the
project experimentation and a statement of how the results relate to the
hypothesis. Reasons for experimental
results that are different to the hypothesis are included. If applicable, the conclusion can end by giving
ideas for further testing.
If your results do not support
your hypothesis:
¡P
DON¡¦T change your hypothesis.
¡P
DON¡¦T leave out experimental results that do not
support your hypothesis.
¡P
DO give possible reasons for the difference
between your hypothesis and the experimental results.
¡P
DO give ways that you can experiment further to
find a solution.
If your results do support your
hypothesis:
You might say, for example, ¡§As
stated in my hypothesis, I believe that light is not necessary during the
germination of bean seeds. My experiment
supports the idea that bean seeds will germinate without light. After seven day, the seeds tested were seen
growing in full light and in no light.
It is possible that some light reached the ¡¥no light¡¦ containers that
were placed in a dark closet. If I were
to improve on this experiment, I would place the ¡¥no light¡¦ containers in a
light-proof box and/or wrap them in light-proof material, such as aluminum
foil.¡¨