Scientific Method: Dr. Herc

1. The Scientific Method refers to the basic steps
scientists use to solve problems…
D • (D)etermine the Problem
R • Gather (R)esearch
H • Form a (H)ypothesis
E • Carry Out an (E)xperiment
R • Record and Analyze the (R)esults
C • Draw a (C)onclusion

2.  A good science problem is written
as a question, and is one that you
can test to find the answer
 *This is the purpose of your
investigation

3.  Gather data to help you form your
hypothesis
 Research what others have already discovered about your
problem (books, magazines, reports, experts, etc.)
 Observation – using one or more of your senses to collect
data
 Inference – an interpretation of an observation based on
evidence or prior knowledge

4.  A hypothesis is a possible explanation of, or
answer to your scientific question
 Worded as an “If…then…because…” statement
 MUST be testable
 MUST be based on research
 Will be supported or disproved by
experimentation

5.  Materials List
 Detailed list of all supplies needed to carry out your
experiment
 Include amounts needed of each supply
 Procedures List
 Step-by-step instructions for how to carry out
experiment
 Must be detailed enough so your experiment could be
repeated by someone else

6.  Controls are things
that do not change
throughout the
experiment
 These are kept the
same throughout
each trial

7.  A variable is a factor that can
change in an experiment
 You may only change one at a time!
 An independent variable is the one and only
variable you’re allowed to change in your
experiment this is the variable being tested (x-axis
on a graph)
 A dependent variable is the factor that changes
because of your independent variable this is the
observed variable (y-axis on a graph)

8.  Now you may design and carry out
an experiment to test your
hypothesis
 Determine controls
 Consider all possible variables
 Must include at least two trials
???

9.  Recording accurate observations and
measurements are necessary to carrying out
a valid experiment
 Once recorded, you can organize your data
 Perform any necessary calculations
 Create charts/graphs/data tables to organize data
 Consider sources of error

10.  Interpret your charts, tables, or graphs to
help you draw your conclusions
 Answer your question using data as evidence
Based on the data you have gathered, were
you able to find the answer to your question?
If so, was your hypothesis correct?
If no, what other experiment(s) could help
you retest your theory?
No octopus
here…

11.  Scientific Theory is
an explanation of how
or why something happens based on
scientific knowledge resulting from repeated
observations and experiments
 A theory is based on thousands of experiments
carried out by many different scientists
 It can be proven to be incorrect as new knowledge
is gained from further experiments

12.  A Scientific Law is a statement about how
something works that seems to be true all of
the time
 Tells what will happen, but does not necessarily
explain why
 Is less likely to change
than a Scientific Theory