Westridge)Science)Fair) Seminar2:E · PDF fileSize$of$football$ Distance$ (in$meters$or$...
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Westridge Science Fair Seminar 2: Experimental Design
Transcript of Westridge)Science)Fair) Seminar2:E · PDF fileSize$of$football$ Distance$ (in$meters$or$...
Westridge Science Fair Seminar 2: Experimental Design
What’s the Next Step?
The heart of the scien.fic method is
EXPERIMENTATION. A<er you’ve decided
on a ques.on to inves.gate, done the
background research and formed your
hypothesis, you can begin to design your
experiment.
Important Terms to Know
Independent variable (IV) -‐The factor that you will change in your experiment. Dependent variable (DV) -‐The factor that you will observe or measure a<er changing the independent variable. Controlled variables (CV)-‐Other factors that can affect the results of your experiment, but that you keep the same for all groups.
Important Terms to Know
Trials – Every .me you perform your experiment it is called a trial. The minimum number of trials to do is three. More trials strengthen your results. VariaFon-‐ Differences in experimental results from different trials are normal and should be expected.
Experimental Design
When designing an experiment to answer your
ques.on, it is important to choose just ONE
independent variable to change and ONE
dependent variable to measure. Otherwise, the
experiment becomes too hard to control and
very difficult to interpret.
Can we iden.fy the independent, dependent
and controlled variables in different
experiments?
Let’s try...
Name That Variable!!!
Experiment IV DV CV
A student wants to sell plants at the farmers market and believes that grow lights will make them grow faster than natural sunlight.
Type of light Plant growth. (height in cm or inches)
Seeds/soil Water Fer.lizer Temperature Time
A student wants to challenge his dad to a throwing contest. He believes that a smaller football will travel farther than a larger football.
Size of football Distance (in meters or feet)
Launcher Wind speed Slope
A student believes that age affects flexibility. She plans to test groups of people to see if they can touch their toes.
Age (groups) Flexibility measured by ability to touch their toes
Gender
Science Project: Required Steps
1) Make a complete list of materials that you will use in your experiment. Include important details about any supplies or equipment that you use. This “Materials” list is required for your presenta.on.
2) A<er you finalize your experimental design, write
down the process in a numbered, step-‐by-‐step list, like a “recipe”, that can be clearly followed by your readers. Anyone should be able to use your instruc.ons to repeat the experiment themselves. This “Procedure” sec.on is also required for your presenta.on.
Examples of “Materials” Lists
Example 1: Plant experiment
Example 2: Ar.ficial hand inven.on
Example of “Methods” or “Procedure”
Diagrams can o<en help illustrate your ideas and processes.
Another Example of a “Procedure” List
Reproducibility
Reproducibility is a VERY important concept in science. It
is the idea that scien.fic results are a real reflec.on of
what actually happens in nature and not some fluke or
weird random occurrence or accident. All good
experiments are ones that can be repeated by the
original scien.st or by others.
Reminders
Date Event
Monday, February 1 Applica.on Deadline
Monday, February 8 No.fica.on of acceptance, work begins
Thursday, February 18 Progress Report 1: Research and Design
Tuesday, March 8 Seminar 3/Progress Report 2
Thursday, March 31 Progress Report 3
Now We Can Start Designing Our Own Experiments
