The Scientific Method

Strand H: The Nature of Science (1. The student uses the scientific processes and habits of mind to solve problems.) Benchmark SC.H.1.2.2 – The student knows that a successful method to explore the natural world is to observe and record, and then analyze and communicate the results. (Annually Assessed – MC, SR, ER)

Sample Science Fair Project

Information on the scientific method used in this example was obtained from www.scifair.org.

1. Select a Topic

Propose a question or problem that can be formulated in terms of a hypothesis that you can test.

How does the outdoor temperature affect energy use?

2. State Your Purpose

What are you trying to discover? Define your variables: one you can control (the independent variable) and one you can accurately measure (the dependent variable) and will change in response to changes in your independent variable. You must also control your other variables or the experiment could be flawed.

Purpose:

I am trying to discover how the outdoor temperature affects electrical energy use in our school. When the difference between inside and outside temperature goes up, what effect does this have on our schools energy use?

3. Do Your Research

What are you experimenting with? Read books, magazines, search the WEB, ask teachers or other professionals. Find out what is already known about your topic. Make sure to keep a reference list on what you found.

References:

1. 50 Simple Things Kids Can Do to Save the Earth, The EarthWorks Group, Andrews and McMeel 1990.

2. No Cost/Low Cost ways to save energy dollars, Advantage Publications and Insights, 1999.

3. Web Site: “Utility Data and Statistics” www.marion.k12.fl.us/dept/emg/dat&stat-pag1.html

4. Web Site: “Energy”

www.projectgreenmachine.org/elec-pag1.html

4. State Your Hypothesis

A hypothesis is a question that has been stated so it can be tested by an experiment. Once stated, you can design an experiment to test it.

Hypothesis:

I think that the electrical energy use at my school will increase as the outside temperature increases.

5. Develop an Experimental Procedure

When developing your experimental procedure you should choose only one element to change – the independent variable. Pick something that will help answer the question and is measurable. Running the experiment without making changes to the variable is called the “control experiment.”

Procedure:

1. Measure temperature – the independent variable.

a. Measure the inside temperature (degrees F) once each day in the afternoon (between 1:30 and 2:00 PM). Place thermometer on the inside wall away from the windows.

b. Measure the outside temperature (degrees F) at the same time (between 1:30 and 2:00 PM).

2. Measure energy use – the dependent variable.

a. Observe the weekly KWH usage from the electric meter each Friday afternoon (between 1:30 and 2:00 PM).

b. Record your observations in the logbook.

3. Record the difference in temperature (Dt) from the inside reading to the outside reading in the logbook each day. Calculate the average Dt for each week and record.

4. Record the weekly KWH usage in the logbook.

5. Graph the results of the weekly KWH usage and average weekly temperature difference (inside/outside).

6. Compare the results to see if there appears to be a relationship between temperature difference and electric use.

* KWH stands for kilowatt-hours, a unit of measure of electric energy used by electric companies.

6. Perform the Experiment and Record Data

Record all measurements that you make on a data table (this is called quantitative data). Make note of any other observations you think might be important (this is called qualitative data). For, example when recording temperature you might record a note that it was raining that day, or that there was a special event being conducted outside that may have caused less need for energy use inside. This might help explain occasions of unexpected results. It might lead to another experimental procedure.

Data: (Meter Constant: 40)
	Date	Time	Meter Unit Reading	Reading Change	Actual KWH	Inside Temp	Outside Temp	D t
	9/12	2:15	25684
	9/19	2:09	26249	565	22600	74	90° F	16°
	9/26	1:59	26751	502	20080	74	85° F	11°

7. Analysis

One of the best ways to analyze your results is to use graphs to show the relationship between the independent and dependent variables. Is there a pattern? Is there a correlation? Does the analysis allow you to draw a conclusion? This graph shows the energy use (scale on the left) compared to temperature difference (scale on the right). The patterns shown by the two graphs seem to match or show a correlation.

Analysis:

(The blue line plots the temperature change and the red line the energy use. You can see that they are closely related. When the temperature goes up, the energy use goes up.)

8. State Your Conclusion

This is where you answer the question you proposed at the beginning of your research. Use the analysis of your experimental data and observations to determine if your hypothesis is correct. Even if you disprove your hypothesis, you still have a good science experiment.

Conclusion:

I conclude by the analysis of the data obtained in this experiment that outside temperature has a direct effect on electrical energy use during school hours. Although not all variables could be isolated, the effect of outside temperature was significant enough to show a noticeable impact on energy use.