Scientific Method
{
Steps of the Scientific Method
1.
Problem
/Question
Develop a
question or
problem that
can be solved
through
experimentation
.
Stating the Problem: Example
What invisible trail does a
rattlesnake follow in tracking
down its bitten prey?
Are all questions good
scientific questions?
Hint: What do you remember the health
department investigative team activity?
* Ex: personal opinion, values, or
judgments.
You be the Judge:
Is this a good testable question
1. Do flying saucers really exist?
2. Which planet is the most interesting
one to study?
3. Which pill design – tablet, caplet, or
capsule will dissolve faster?
4. How much your pet “loves” you
5. If you went “back” in time what would
happen with a different decision
6. If students behavior is related to getting
an A in the class then behaving nice will
result in more As.
2.
Hypothesis
Predict a possible
testable answer to
the problem or
question.
•
Your hypothesis
is NOT a fact
•
Worded as an If. .
. Then statement
Example: If soil
temperatures rise,
then plant growth
will increase.
Hypothesis Example
If a snake wounds its victim, then the
snake follows the smell of its own venom
to locate the animal
Creating a Hypothesis
from testable questions
1. What type of pizza is preferred by
fourth graders?
2. How does the amount of daylight
affect how many eggs laid by a chicken?
3. How does room temperature affect
student performance?
4. How will batting practice affect a
players batting average?
Monty Python- witch scene hypothesis
Hypothesis: HW
1.
2.
3.
4.
5.
Chocolate may cause pimples.
Salt in soil may affect plant
growth.
Plant growth may be affected by
the color of light.
Bacterial growth may be affected
by temperature.
Ultraviolet light may cause skin
cancer.
3.
Experiment
Develop and follow
a procedure. (list
of each step)
Experiment: Example
Drag a dead mouse that has been
struck and poisoned by a rattlesnake
along a curved path on the bottom of an
empty cage
 Place the snake in the cage
 The snake follows the exact trail that
has been laid out
 Drag an unbitten dead mouse along the
path
 The snake seems disinterested

4.
Collect and
Analyze
Data/Graph
5.
Conclusion



Include tables, graphs,
and photographs
statement based on
the results of the
experiment.
Include a statement
that accepts or
rejects the
hypothesis and
recommend possible
improvements to the
procedure.
Conclusion: Example
The scent of venom
was the only factor
that could cause a
rattlesnake to follow
its bitten victim.

6.
Communicate
the Results
Mr. Lee- Scientific Method Song
Setting Up a Good
Experiment: Parts that are
necessary.
Observation:
Quantitative
#
Qualitative
Y
Qualitative
▪

Measurements:
(numbers) Scales,
Rulers, Balances
Qualities:
(characteristics)
smell, look, hear,
touch, taste
looks
Quality/Qualitative
Word
Quality
(noun)
Meaning
DFN: Essential character;
distinguishing attribute;
characteristic; superiority in
kind
SYN: 1. Characteristic,
feature; 2. superiority,
excellence
Examples
Oral Practice
1. A quality of many mobile 1. A quality of a good friend
telephones is that they have is ________.
a keyboard.
.
2. Quality food is fresh and
taste good.
Writing Practice: The most important ________________ of a great cell phone is
__________________________ because it allows you to _____________________________________.
Qualitative
(adj)
DFN: pertaining to or
concerned with quality or
qualities; involving
distinctions based on
characteristics;
SYN: none
1. Burning a log causes a
qualitative change in its
appearance.
1. A qualitative characteristic
of your hair is that it is
______________________.
2. The doctor used the
qualitative observations of
skin redness to determine
that the patient had a rash.
Writing Practice: __________________ data that a scientist would collect when observing birds in their
natural environment might be _______________________________________________.
Control
Parameter
What is kept the same
in an experiment
•
Way to remember:
how does the school
try to control you?
(how you dress to
make you look the
same). . .
•
Example: No hats in
classes

What is the control parameter?
Shaq
Shaq wanted
wanted to
to find
find out
out how
how
basketball
basketball filled
filled with
with different
different
substances
substances would
would help
help his
his freefreethrow.
throw. He
He uses
uses the
the same
same ball,
ball,
same
same pressure,
pressure, and
and same
same spot
spot
where
where he
he threw
threw the
the ball.
ball. He
He
changes
changes what
what is
is in
in the
the ball
ball
helium,
helium, nitrogen,
nitrogen, and
and oxygen.
oxygen.
What is the control parameter?
Samantha wanted to find out
how elevation affects car
speed. She use the same car,
ramp, release point for each of
the trials. She only changed
the elevation of the ramp.
Quality/Qualitative
Word
Variable
(noun)
Meaning
Examples
Oral Practice
DFN:
a. The variable in our
Something that _______
a. Something that varies or
experiment is the
each time you look at it
is prone to variation.
volume of liquid are
might be called a variable.
b. Mathematics: A quality
heating..
capable of assuming any of b. In the expression a2 +
a set of values.
b2 = c2, a, b, and c are
variables.
SYN: 1. Characteristic,
c. The piece of information
feature; 2. superiority,
plotted on a graph are
excellence
called variables
Variable
(adj)
DFN:
a. Our weather has been
a. Likely to change or vary; quite variable lately, warm
subject to variation;
one day, cool the next.
changeable
b. Mathematics: having no
fixed quantitative value.
SYN: Changeable
ANT: Constant, Unchanging
Writing Practice: It is really important to record about the variables in an experiment because
_______________________________.
Independent
Variable



One thing you are
changing in an
experiment
(different)
Also called
manipulated
variable
Goes on x-axis for
graphs
What is the independent variable?
Shaq wanted to find out how
basketball filled with different
substances would help his freethrow. He uses the same ball,
same pressure, and same spot
where he threw the ball. He
changes what is in the ball
helium, nitrogen, and oxygen.
What is the independent variable?
Samantha wanted to find out
how elevation affects car
speed. She use the same car,
ramp, release point for each of
the trials. She only changed
the elevation of the ramp.
Why do you think it is
important to have ONE
independent variable?

Dependent
Variable
observed or
measured.
(It is the result of
changing the
independent
variable.)



Also called
Responding Variable
Goes on y-axis for
graphs
What is the dependent variable?
Shaq wanted to find out how
basketball filled with different
substances would help his freethrow. He uses the same ball,
same pressure, and same spot
where he threw the ball. He
changes what is in the ball
helium, nitrogen, and oxygen.
What is the independent variable?
Samantha wanted to find out
how elevation affects car
speed. She use the same car,
ramp, release point for each of
the trials. She only changed
the elevation of the ramp.
For the Rainbow lab
what is the
Independent Variable
and Dependent
Variable for that lab?

Identify control
parameters,
independent variable
and dependent
variable
John watches his grandmother
bake bread. He ask his grandmother
what makes the bread rise. She
explains that yeast releases a gas as
it feeds on sugar. John wonders if the
amount of sugar used in the recipe
will affect the size of the bread loaf?
John adds the same amount of flour,
salt, milk, and cooks it in the same
oven. He performs the experiment.
After talking with his teacher and
conducting further research, he
comes up with a hypothesis. “If more
sugar is added, then the bread will
rise higher.”
Humpty
Dumpty had a problem falling
off of walls. He decided to see which
harness could keep him on top of the
wall the longest. He used the same
location, weather, and daily activity of
sitting on the wall. He tried five
different harnesses (save o lot, crack
b no more, safety, harness of life, and
scrambled eggs no more).
Summarize in your own
words the difference
between independent
and dependent variable
Variable Identification Worksheet 1:
A scientist is doing an experiment to see what type of sugar
makes cells grow faster. The data tables below show what is
added to each test tube and the number of cells over time.
Numberof
of Milliliters
Milliliters
Grams
Type
Number
ofof Grams
of of Type
ofof
Test
Tube
Test Tube
cellsadded
added
water
sugar
sugar
cells
water
sugar
sugar
1
1
2
2
1000
1000
1000
1000
100
100
100
100
5 5
5 5
fructose
fructose
sucrose
sucrose
3
3
4
4
1000
1000
1000
1000
100
100
100
100
5 5
5 5
equal
equal
glucose
glucose
Number of
of cells
cells test
test tube
tube with:
with:
Number
Fructose
Sucrose
Equal
Glucose
Fructose
Sucrose
Equal
Glucose
Controlled
Parameters:
Day
Day
1
1,000cells
1,000
1,000
1,000
1
1,000
1,000
1,000
1,000
Number
of
added,
2
2,000
2,000
900
2,000
2
2,000
2,000
900
2,000
Milliliters
of water,
grams
3
4,000
4,000 and
800
4,000
3
4,000
4,000
800
4,000
8,000
8,000
700
8,000
8,000
700
8,000
of 445sugar8,000
16,000
16,000
600
16,000
5
16,000
16,000
600
16,000
Variable Identification Worksheet 1:
A scientist is doing an experiment to see what type of sugar
makes cells grow faster. The data tables below show what is
added to each test tube and the number of cells over time.
Test Tube
Number of Milliliters of
cells added
water
Grams of
sugar
Type of
sugar
1
1000
100
5
fructose
2
1000
100
5
sucrose
3
1000
100
5
equal
4
1000
100
5
glucose
Independent
Variable:
Day
Fructose
Sucrose
Equal
1
1,000
1,000
1,000
Type
of Sugar
Number of cells test tube with:
Glucose
1,000
2
2,000
2,000
900
2,000
3
4,000
4,000
800
4,000
4
8,000
8,000
700
8,000
5
16,000
16,000
600
16,000
Variable Identification Worksheet 1:
A scientist is doing an experiment to see what type of sugar
makes cells grow faster. The data tables below show what is
added to each test tube and the number of cells over time.
Test Tube
1
Number of Milliliters of
cells added
water
1000
100
Grams of
sugar
Type of
sugar
5
fructose
2
1000 Variable:
100
5
sucrose
Dependent
Number
of
3
1000
100
5
equal
Cells
4
1000
100
5
glucose
Number of cells test tube with:
Day
Fructose
Sucrose
Equal
Glucose
1
1,000
1,000
1,000
1,000
2
2,000
2,000
900
2,000
3
4,000
4,000
800
4,000
4
8,000
8,000
700
8,000
5
16,000
16,000
600
16,000
4. Two students want to see which paper
airplane will travel farther. They used the
same type of paper, same color, same
size, and the dart design. One student put
airplane.
a paper clip on the nose of his airplane.
The other student does not.
Controlled
Parameter
Type of paper
Color
Size
Dart Design
Independent
Variable
Paper clip on
nose
Dependent
Variable
Travel farther
5. A
A class
class of
of students
students wants
wants to
to figure
figure out
out what
what makes
makes cut
cut
5.
roses last
last longer
longer and
and look
look prettier.
prettier. The
The students
students decide
decide to
to use
use
roses
red roses
roses with
with a
a 10
10 centimeter
centimeter stem
stem length
length from
from the
the same
same type
type
red
of rose
rose plant
plant grown
grown in
in the
the same
same nursery.
nursery. They
They put
put the
the roses
roses in
in
of
the same
same size
size of
of vase
vase filled
filled with
with Aquafina
Aquafina water.
water. To
To each
each vase
vase
the
they add
add 10
10 grams
grams of
of a
a different
different substance:
substance: sugar,
sugar, salt,
salt,
they
caffeine, baking
baking soda,
soda, vinegar,
vinegar, fertilizer,
fertilizer, and
and one
one vase
vase has
has
caffeine,
nothing added
added to
to it.
it. They
They wait
wait to
to see
see which
which rose
rose lasts
lasts longer.
longer.
nothing
Controlled
Parameter
Stem Length
Type of Rose
Nursery
Vase
Aquafina
water
10 grams
Independent
Variable
Different
substance
Dependent
Variable
Last longer
6. A group of students want to determine which laundry
soap works the best. They take 6 exactly the same
socks (men's Haines) and put one half cup of oil on the
bottom of the sock and let it dry. They then wash each
sock separately using one fourth cup of their detergent to
see which got cleaner. They tested Shout, Bleach, Tide,
Downey, and Gain. One sock is washed only with water
and no soap.
Controlled
Parameter
Sock
Oil amount
Oil Location
Socks Dried
Independent
Variable
Detergent
Dependent
Variable
Works best
(cleaner)
7.
7. A
A veterinarian
veterinarian is
is testing
testing out
out dog
dog food
food in
in order
order to
to determine
determine
which
which dog
dog food
food helps
helps dogs
dogs to
to lose
lose weight
weight the
the fastest
fastest while
while still
still
giving
giving enough
enough nutrition.
nutrition. He
He takes
takes 10
10 dogs
dogs of
of the
the same
same weight
weight
and
and breed
breed and
and puts
puts each
each of
of them
them on
on a
a diet
diet for
for 6
6 months.
months. Each
Each
dog
dog is
is given
given 1/2
1/2 gallon
gallon of
of water
water each
each day
day and
and 6
6 cups
cups of
of dog
dog
food
food of
of the
the different
different kinds.
kinds. The
The dogs
dogs are
are kept
kept in
in cages
cages to
to
control
control their
their amount
amount of
of exercise
exercise and
and are
are walked
walked twice
twice daily
daily
(morning,
(morning, night)
night) for
for 30
30 minutes
minutes each
each time.
time. The
The dogs
dogs weight
weight is
is
measured
measured each
each night
night at
at the
the same
same time.
time.
Controlled
Parameter
10 dogs of same
weight and breed
Diet 6 months
½ gallon water
6 cups dog food
Cages (exercise)
Walked 2 x a day 30
0mun
Weight same time
Independent
Variable
Dependent
Variable
Different
kinds of dog
food
Lose weight
the fastest
Variables from Hypothesis
If temperature increases then leave colors
will change.
Independent Variable
Dependent Variable
*in front in if then statement and dependent is
after then.
1. If there is high temperature
then it will cause an increase in
radish germination.
2. If you study with music then
your test scores will increase.
3. If food coloring is added to
fish food then the fish will die.
Reproducible
Data that is around the same
Data
number.
Example:
An experiment is done and if
you get the same answer
over and over again the data
is considered reproducible.
Are the following
reproducible results?
Example 1:
1, 10, 1, 1.0, 1.111
Example 2:
2.0, 1.999,2.01
Example 3:
3.0, 30, 3.3, 30.0
What makes something
reproducible?
Does this show reproducible?
Example: 1.
Trial
1
2
3
Average
Time
(seconds)
12. 2
11.3
7.9
11.9
Speed
Averages
(meters/second)
3.0
4.07
3.3
3.42
1.8
4.39
2.4
4.96
Time
(seconds)
4.9
5.0
4.8
4.9
Speed
(meters/second) Averages
4.9
1.0
5.56
.9
4.36
1.1
4.9
1.0
Example 2.
Trial
1
2
3
Average
Does this show reproducible?
Example: 3.
Trial
1
2
3
Average
Time
(seconds)
102.9
45.9
30.5
59.8
Speed
(meters/second) Averages
51.49
2.00
22.95
2
15.25
2
29.9
2
Create a chart that shows
reproducible data
Trial
1
2
3
Average
Time (seconds)
Speed
(meters/second)
The volume of an object is 10 mL.
Several students measure its volume
with a graduated cylinder. Is the data
reproducible? Accurate?
George
Trial
1
2
3
Average
Volume
10.0 mL
10.0 mL
10.0 mL
10.0 mL
Shelly
Trial
1
2
3
Average
Sara
Trial
1
2
3
Average
Volume
3.0 mL
2.99 mL
3.01 mL
3.0 mL
Kevin
Volume
2.0 mL
16.0 mL
12.0 mL
10.0 mL
Trial
1
2
3
Average
Volume
9.9 mL
10.1 mL
10.0 mL
10.0 mL
Evaluating Experimental
Design
Scenario: A group of students wanted to
find out what stain removing substance
will take away a stain the best .
Mud stain
1 T Remover
1 gallon water
½ day line dry
1. Controlled
Parameter (s)
Mud stain
1 T Remover
1 gallon water
½ day line dry
Mud stain
1 T Remover
1 gallon water
½ day line dry
2. Independent
Variable (s)
Mud stain
1 T Remover
1 gallon water
½ day line dry
3. Dependent
Variable(s)
Scenario: A group of students wanted to
find out what stain removing substance
will take away a stain the best .
Mud stain
1 T Remover
1 gallon water
½ day line dry
Mud stain
1 T Remover
1 gallon water
½ day line dry
Mud stain
1 T Remover
1 gallon water
½ day line dry
4.Design Flaw:
5. How would you redesign the
experiment so its ore controlled:
Mud stain
1 T Remover
1 gallon water
½ day line dry
Scenario: A group of students wanted to
see what grows mold the best.
5g Bread
In Cupboard
1. Controlled
Parameter (s)
5g Apple
In Cupboard
5g Macaroni
In Cupboard
2. Independent
Variable (s)
5kg Lettuce
In Cupboard
3. Dependent
Variable(s)
Scenario: A group of students wanted to
see what grows mold the best.
5g Bread
In Cupboard
5g Apple
In Cupboard
5g Macaroni
In Cupboard
5kg Lettuce
In Cupboard
4.Design Flaw:
5. How would you redesign the
experiment so its ore controlled:
Evaluating Experimental
Design Worksheet
Experiment 1: A group of students want to test red flowers to see how
pot size affects plant growth. They place the red flowers in brown clay
pots and give all of the plants 1 cup of dirt, 1 cup of water each day,
and place them by the window. The students will then measure the
growth of the plant over a period of 4 months.
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1. Controlled Parameters
2. Independent Variable(s) 3. Dependent Variable(s)
__________________
__________________
__________________
__________________
___________________
___________________
___________________
___________________
___________________
___________________
___________________
___________________
___________________
___________________
___________________
4. Design Flaw:
5. How would you redesign the experiment so its more controlled:
Experiment 1: A group of students want to test red flowers to see how
pot size affects plant growth. They place the red flowers in brown clay
pots and give all of the plants 1 cup of dirt, 1 cup of water each day,
and place them by the window. The students will then measure the
growth of the plant over a period of 4 months.
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1. Controlled Parameters
Red flower
Brown clay pot
1 cup dirt
1 cup water
By window
Period (4 months)
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
1 cup dirt
1 cup water
window
2. Independent Variable(s) 3. Dependent Variable(s)
Pot size
Leaves
Growth of plant
4. Design Flaw: Too many independent variables
5. How would you redesign the experiment
experiment:so its ore controlled: Choose plants that have
the same amount of leaves
Experiment 2: A group of students want to test how medium orange
colored goldfish get along with other colors of goldfish. (use your
C
Tank D
imagination that goldfishTank
can
come in other colors ) They
put one
goldfish in a glass 5 gallon of water fish tank. They then put in another
color of gold fish. Each tank has one plant and one rock sculpture of
the same size.
Tank A
Tank B
6. Controlled Parameters
__________________
__________________
__________________
__________________
__________________
__________________
__________________
Tank C
7. Independent Variable(s)
___________________
___________________
___________________
___________________
___________________
___________________
___________________
9. Design Flaw:
10. How would you redesign the experiment:
Tank D
8. Dependent Variable(s)
___________________
___________________
___________________
___________________
___________________
___________________
___________________
Experiment 2: A group of students want to test how medium orange
colored goldfish get along with other colors of goldfish. (use your
C
Tank D
imagination that goldfishTank
can
come in other colors ) They
put one
goldfish in a glass 5 gallon of water fish tank. They then put in another
color of gold fish. Each tank has one plant and one rock sculpture of
the same size.
Tank A
Tank B
6. Controlled Parameters
Glass tank
5 gallon of water
Plant
Rock sculpture
Tank C
Tank D
7. Independent Variable(s) 8. Dependent Variable(s)
Different colored
Different sizes
Get Along
9. Design
Design Flaw:
Flaw: Too many independent variables
9.
10. How
How would
would you
you redesign
redesign the
the experiment:
experiment: Check mass of each goldfish and make sure
10.
it’s the same