The scientific method involves 6 key steps: 1) stating the research problem and questions, 2) formulating hypotheses, 3) testing hypotheses by gathering data through experimentation, 4) analyzing and presenting the experimental data, 5) drawing conclusions based on the results, and 6) reporting findings. The experimenter identifies an independent variable to change, a dependent variable to measure the effects of changes, and keeps all other potential factors constant as controlled variables. The goal is to determine the effect of the independent variable on the dependent variable.

1. SCIENTIFIC
METHOD

2. Objectives:
Describe the components of a scientific
method.
Follow the steps of the scientific method in
performing an experiment.
Conduct simple investigation using process
involving community-based problem using
locally available materials.

3. Scientific Method
 is the key to unlock the bodies
of knowledge.
 It helps man to magnify truth
about the things around him.
 is use to answer specific
questions.

4. In order to understand the Scientific
Method, we first need to understand
what a
VARIABLE
is

5. –anything in an experiment
that can change.

6. You want to design a car that will roll down
a ramp really fast.
So you need to know what things affect how fast
a car will roll down a ramp.
What could you change about
this car or ramp that might
affect its speed?

7. Yes, what could you change or
do to make the car go fasteris
theramp.
These ideas all make up
something we call:

8. variables

10. Three main kinds of variables
1. Independent variable
2. Dependent variables
3. Controlled variables

11. 1. The independent variable is:
• The variable that you change or
alter during the experiment.
• There can only be one change
variable in any experiment.

12. In the experiment on the next slide,
identify the independent/change
variable—what is the one thing the
experimenter changed with plant 1, 2 and
3?

13. No Water
Plant 1 Plant 2 Plant 3
20 mL
Water
every
day
40 mL
Water
every
day

14. Yes, the experiment changed the
amount of water that the plant
receives each day.

15. 2. The dependent/ responding variable
is what measured or observed by the
experimenter to see if the independent
variable caused a different result.
Ex. (goes faster, grows taller, warms up more, etc.)
depends on the change (or independent) variable.

16. Let’s look again at the experiment where
the amount of water each plant received
was changed.
What could the experimenter observe
or measure to see if the amount of
water made a difference to the health
of the plant?

17. No Water
Plant 1 Plant 2 Plant 3
20 mL
Water
every
day
40 mL
Water
every
day

18. The experimenter could have, for
example, counted the number of green
leaves on each plant or he could have
measured the height of the plants after 14
days.

19. Some examples of dependent/responding variables
in
in different experiments— things to be
observed or measured are:
The amount of water absorbed by two different
brands of paper towels.
How far a ball rolls from different ramp
angles.
The amount of feed eaten at a bird feeder in
response to the type of seed in the feeder.

20. Whenever possible the experimenter should
measure, instead of just observing, the
dependent variable.
In order to measure the dependent variable
the experimenter uses tools such as

21. a metric ruler or meter stick
To measure how far something moved.

22. balance scale
to measure the mass of something

23. thermometer
To measure how hot or
cold something is

24. PLASTIC
CUP OF
HOT
WATER
STYROFOAM
CUP OF HOT
WATER
What might be the independent variable be in this experiment
on keeping water hot?
What might be the dependent variable in this experiment?
Remember you should measure.

25. What would be the
independent
variable in this
experiment on how
much heat different
soils absorb?
What could be the
dependent variable in
this experiment?
Remember you
should measure.

26. To use the scientific method to answer
questions, we set up an experiment that
changes just one thing and then we measure
how that one change affects what we are
interested in.
The question is always “what is
the effect of independent variable on
dependent variable”?

27. No Water
Plant 1 Plant 2 Plant 3
20 mL
Water
every
day
40 mL
Water
every
day

28. For example, in the case of our watering
plants experiment, the question might be:
How does the amount of water you give a plant
(independent variable) affect how tall the
plant grows. (dependent variable)?

29. But there is more. In every experiment
there is a third kind of variable called
the controlled variable.
Control variables are all those things in
an experiment that you do not let
change or kept constant.

30. •A control variable is any other variable
(other than the change variable) that might
affect the outcome of the experiment.
• There may be many control
variables in any experiment

31. Think back to our experiment asking the
question: “How does the amount of water
affect how tall the plant grows in 14 days?”
What variables, other than the amount of
water, could affect how tall the plant
grows?

32. No Water
Plant 1 Plant 2 Plant 3
20 mL
Water
every
day
40 mL
Water
every
day

33. Things that might affect how
tall the plant grows could include:
1. the amount of light
2. the temperature of the air
3. the kind of soil

34. What would be the problem if we
changed both the amount of water
and the type of soil the plant is
growing in at the same time?
Sure, you wouldn’t know if the
growth was due to the water or the
type of soil.

35. Plant 3
Plant 1 Plant 2
20 mL
Water every
day
No Water
40 mL
Water every
day
Sandy soil Clay soil Potting soil

36. Suppose the plant in the potting soil
that was given 40 mL of water daily
grew the tallest after 14 days?
Could we know whether the 40 mL of
water or planting the plant in potting
soil had caused the results?

37. Probably not: In order to make correct
conclusions when doing experiments we
must:
• have only one change/independent
variable and
• control all other variables
that might affect the results— keep them
constant through out the experiment.

39. Components of a Scientific Method:
1.Statement of the Research Problem
- answers the following questions:
a. What questions do you have
about your topic?
b. What do you want to know?
Example:
How does fertilizer affect the growth of plants?

40. 2. Formulation of Hypothesis
 Hypothesis is a simple statement that presents the possible
solution to the problem. It can be stated in two ways:
1. Null hypothesis (Ho) – hypothesis that states a no relationship
between variables.
Example:
The fertilizer does not affect the growth of plants.

41. 2. Alternative hypothesis ( Ha) –
hypothesis that states a relationship between
variables.
Example:
There is significant relationship between the
growth of plants and the use of fertilizer.

42. 3. Testing Hypothesis/ Gathering of data
 At this point you are ready to test your hypothesis by
conducting an experimentation.
Experiment is a set of manipulations or specific
observations of nature, and it is considered the most
important part of the scientific method.
Three types of experiments:
1. controlled experiment
2. natural or quasi experiment
3. field experiment

43. Gathering of Data
- research, read information related to the
problem, interview, and consult experts.

44. 4. Analyzing and presenting Data
Data obtained from the experiments should
be analyzed and presented systematically
using a table for easy interpretation.

45. 4. Creating Conclusion
 Conclusion is a summary of the results of the
experiment and the statement of how the results match
up to the hypothesis.
 * theory – if a good conclusion has been tested often
enough and showed valid and reliable
results.(scientifically accepted)
 * scientific law – a theory that has been tested and
confirmed by various experiments (universally
accepted)
6. Reporting of findings – share the results.

47. Review
1.Change variable—the thing the
experimenter changes on purpose.
2.Responding variable-- what the experimenter
observes or measures to see if the change
variable is making a difference.
3.The control variable—the other things that
could cause the responding variable to change—
must be kept the same.

48. Scientific Methods
1.Statement of the Research Problem
2.Formulation of Hypothesis
3.Testing Hypothesis and gathering data
4.Analyzing and Presenting Data
5.Creating Conclusion
6.Reporting of findings