Scientific Method
The process to conduct scientific
investigations
What is the Scientific Method?
 The Scientific Method is a process
used to find answers to questions
about the world around us
• There are several versions
• No matter which version is used, all
begin with a testable question and
provide an organized method for
conducting and analyzing an
experiment
So How Many Steps?
 There are six steps in our method
 This will help you remember:
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SIX
GREAT
FARMERS
PLANT
ALL
DAY
What are the Steps?
State the Problem
Great: Gather Information
Farmers: Form Hypothesis
Plant: Perform Experiment
All: Analyze Data
Day: Draw Conclusions
 Six:
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SIX: State the Problem
• What do you want to know or
explain?
• Your problem must be in the form of
a question and include the
independent variable and dependent
variable
• Does (the) ________affect ____________?
(independent variable)
(dependent variable)
GREAT: Gather Information
 You should research the scientific
concepts associated with the
experiment
 For example, if you are testing to
see which paper towel brand is the
most absorbent, you should research
absorbency, paper material, and
quality control testing. This will help
answer the “WHY?”
GREAT: Gather Information (cont’)
 DO NOT LOOK FOR THE ANSWER TO YOUR
POSSIBLE SCIENCE PROBLEM, look for:
 General background information
 Definitions of words related to your topic
 Statistics – results from other similar
scientific experiments
 Examples
 Scientists/people related to your chosen
topic
FARMERS: Form Hypothesis
 Remember a hypothesis is an
“educated guess.”
 After doing research on your topic
and coming up with a question or
problem to investigate, you now
have the tools to make an “educated
guess.”
FARMERS: Form Hypothesis (con’t)
 Your hypothesis should follow the format
If (the) ________, then ____________.
(independent variable) affects the (dependent variable)
 DO NOT use words such as best, better,
bigger, smaller
 Use words that are measurable
FARMERS: Form Hypothesis (con’t)
Great Examples:
 If the size of a meteorite affects the
circumference of a crater, then the
larger the meteorite, the larger the
crater.
 If the type of liquid affects the growth of
a plant, then orange juice will help the
plant grow tallest.
PLANT: Perform Experiment
 To successfully carry out an
experiment, your experimental
design must include the following:
 materials list
 step-by-step procedure
 list of the experimental control;
independent, dependent &
controlled variables
 list of safety precautions
Perform Experiment - Materials
 Must be in a list form (no sentences)
 Must include all equipment and
supplies needed to carry out the
experiment
 Remember this list might change
when you actually perform your
experiment. This list is what you
think you may need. It can always
be updated.
Perform Experiment – Materials
(con’t)
 Must include size of items
 Must include amount of each item
needed
 Example:
9 radish seeds
15 cups of potting soil
25 mL of tap water
1 graduated cylinder
3 four-inch flower pots
25 mL of vinegar
25 mL of orange juice
1 metric ruler
Perform Experiment – Procedure
 Step-by-step directions
 One step at a time
 Steps must be very specific
 Steps must be numbered
 You do not need to say “Collect
materials”, it is assumed you will do
that.
Perform Experiment – Procedure
(con’t)
 Include what you are measuring
(dependent variable) and how often you
will be measuring
 Your experiment must include at least 3
trials
Perform Experiment – Procedure
(con’t)
 DO NOT ever include the statement
“RECORD RESULTS.” This statement
means nothing.
 Rather than say “record results” write
“record height, length, etc”
 You are recording a measurement,
which are your results
 BE SPECIFIC!
Procedure Example
1.
Label 3 four-inch flower pots – one vinegar, one orange juice, one
water.
2.
Fill each flower pot with 5 cups of potting soil.
3.
Place 2 radish seeds in each of the pots.
4.
Water the pot labeled vinegar with 10 mL of vinegar.
5.
Water the pot labeled orange juice with 10 mL of orange juice.
6.
Water the pot labeled water with 10 mL of water.
7.
Place the three pots near a window.
8.
Measure the height of the growing radish seeds every other day for 4
weeks.
9.
Use a metric ruler to measure the heights of all the growing seeds.
10. Record all the heights in a table.
11. Also records several observations of the growing radish seeds each
day you measure the plants.
12. Record these observations in a separate table.
Perform Experiment – Control &
Variables
 Experimental Control – the part of the
experiment that is used as the “normal”
or “comparison” so that you can
compare it to the independent variable
 Examples include a plant by the
window or a plant watered with water
Perform Experiment – Control &
Variables (con’t)
 Independent Variable – the part of the
experiment you are changing or testing
 Ex: types of liquid or number of seeds
 Dependent Variable – the part of the
experiment that your are measuring
 Ex: plant height (mm) or leaf length
(mm)
Perform Experiment – Control &
Variables (con’t)
 Controlled variables – parts of the
experiment that never change, such
as:
 same number of seeds
 same amount and type of soil
 same size pot
 same amount of sunlight, etc.
S.U.N.S.E.T.
 Size
 Unique qualities
 Number of parts
 Shape
 Exact colors
 Texture
ALL: Analyze Data
 Your results should include three
parts:
 A table of data (numbers)
 A graph of averages or final results
 A paragraph of detailed qualitative
observations taken during the
experiment
Analyze Data – Data Table
 Includes title
 Organized information with labeled
columns and rows
 Proper units included with measurement
 Must include results of ALL trials
Data Table Example
Number of Chocolate Chips in Different Brands of Cookies
Brand
Chips Ahoy!
Original
Chips Ahoy!
Chewy
Chips
Deluxe
# Chips
Trial 1
# Chips
Trial 2
# Chips
Trial 3
# Chips
Trial AVG
28
30
32
30
34
30
22
28.6
32
38
40
36.6
Analyze Data – Graph
 Include title
 Include labels for both axes with
proper metric units
 Include correct scale for axes
 Include a key or legend if needed
Analyze Data – Graph
(con’t)
 Choose correct type of graph for your
final results
 Bar graph – used for comparison
 Line graph – used to show change over
time
 Pie or circle graph – used to show parts
of a whole (percentage)
Analyze Data – Graph
(con’t)
Problem: Does the INDEPENDENT VARIABLE
affect the DEPENDENT VARIABLE?
measurement units
dependent variable
Y-axis
independent variable
measurement units
X-axis
Analyze Data - Paragraph of
detailed qualitative observations
 One to two paragraphs of what you saw,
heard, felt, or smelled during the
experiment
 Notes of your observations should be
written down as you are performing your
experiment
Analyze Data – Paragraph
(con’t)
 After the experiment, write up your
notes into a paragraph or two.
 NO OPINIONS – only what happened
during the experiment, about the
experiment.
 NO CONCLUSION statements – nothing
about your quantitative observations
DAY: Draw Conclusions
 All of the following must be used to
create a complete conclusion:
 Restatement of your problem
 Restatement of your hypothesis
 General statement of the final
average results of your trials. DO
NOT restate the results of each
and every trial. That information
is already in your data table.
Averages are a good summary.
DAY: Draw Conclusions
(con’t)
 General patterns or trends found in
your analysis of results.
 A sentence which states if your
hypothesis was accepted (correct) or
rejected (wrong).
 Answer to the problem.
DAY: Draw Conclusions
(con’t)
 A list of factors that may have
affected the results of your project.
 A general statement of what the
experiment taught you and how
what you learned can be connected
to the real world or your life.
Conclusion Example
For my experiment, I wanted to find out if different kinds of
household liquids would affect the growth of radish seeds. I
thought that if radish seeds were grown in vinegar, they would
grow taller than seeds grown in water or orange juice. According
to my results, radishes watered with vinegar grew to an average
height of 15.6 cm, radishes watered with water grew to an
average height of 23.4 cm, and radishes watered with orange juice
grew to an average height of 10.1 cm. Therefore, my hypothesis
was rejected. Vinegar did not help the radish seeds grow taller.
In conclusion, radish seeds grown in water grew the tallest, while
radish seeds grown in orange juice grew the shortest. Several
factors may have affected the results of my experiment. During
the experiment, one of the seeds watered in vinegar died after 3
days, leaving only one plant for vinegar. In addition, after 7 days,
the radishes in orange juice grew blue mold and it did not smell
very good. From this experiment, I learned that if I want to grow
large, healthy radishes, I should water the seeds with water, not
vinegar or orange juice.
Scientific Method
Any
Questions?
References
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http://www.sciencebuddies.org/science-fairprojects/project_data_analysis.shtml
Ms. Sue Fortin, Science teacher – Coelho Middle School