Scientific Method- Grade 7

1. SCIENTIFIC
METHOD

5. V O S L E

6. S G U E S

7. Science has been an inevitable
part of life. For centuries, it
had shaped all aspects of life,
explained various phenomena,
and contributed countless
discoveries, ascertained
governing principles and laws
of nature and many more.

8. Anthony’s Experiment
Ms. Gatdula was invited by a friend to visit her in Baguio City. Before leaving her home in Lucena,
she instructed her helper to feed the fish in the aquarium during her absence.
It was May. The summer heat was almost unbearable. The helper was worried about the fish
entrusted to her. One very warm afternoon, she got a tray of ice cubes and put all of them into the
aquarium. In just a short while, all the fish in the aquarium died.
Anthony, a nephew of Ms. Gatdula, learned about the tragic incident. But he did not reprimand the
helper right away. He wanted to be sure of the cause of death of the fish. Here is what he did:
• He bought six fish of the same kind as those that had died. He kept them in the aquarium for two
days.
• He got two large wide-mouthed glass jars of the same size. He labeled one “Jar no. 1” and the other
“Jar no. 2”. He put the same amount of water in the jars, and three fishes in each jar, together with some
aquarium plants and pebbles.
• When the fishes have stayed in the jar for two days, he put ice cubes in Jar no. 1.
• He observed that the fishes in Jar no. 1 died and those in Jar no. 2 did not.

9. 1. Who are the main characters in the story?
2. What tragic incident occurred in the story?
3. What did Anthony suspect that might have
caused this tragic incident?
4. What did Anthony do in order to prove his
suspicion?
5. What did Anthony find out? Is his suspicion
correct?

10. Scientific method is the
mathematical and experimental
technique employed in the
sciences and scientific
investigations. More specifically, it
is the technique used in the
construction and testing of a
scientific hypothesis

11. P for Problem – stating a problem/
identifying a problem. A problem can be
identified after a thorough observation or
relying on existing data . In observing we
have to use our 5 senses to gain
information. After observation comes a
question, which is now your statement of
the problem. A good scientist will ask lots of
questions.

12. D for Data – gathering of data in
a form of research, interview or
existing data.

15. H for Hypothesis – formulating
hypothesis (scientific guess/
educated guess)

16. E for Experiment –testing the
hypothesis An experiment is a test that
will prove or disprove the hypothesis. A
good scientist will conduct an experiment
more than once to double-check their
work.
In testing, variables are of great
importance. A variable is any item, factor,
or condition that can be controlled or
changed.

17. . C for Conclusion – Make a
statement that accept or reject
the hypothesis. The scientist
will report his or her findings so
that others may know what
they find out.

18. A for application – Putting
something into use/operation
based from the outcome of the
experiment

20. In the story, a research problem presented itself when Ms. Gatdula’s
aquarium fish died. Anthony then made observations and gathered
information about the incident, and learned that the helper has put some
ice into the aquarium. From this information, Anthony hypothesized that it
must have been due to the sudden change in temperature of the water
because of the ice cubes. Anthony then came up with a method to test his
hypothesis. He conducted an experiment.
Then, with the evidences from his experiment, he was able to draw a
conclusion that the death of the fish was in fact due to the sudden change in
temperature of the water following the addition of the ice cubes.
His hypothesis was correct.

21. I. Multiple Choice: Read each item carefully and encircle the letter of your answer.
1. _____ is a series of steps designed to help you solve problems and answer questions.
a. experiment b. hypothesis c. scientific investigation d. observation
2. In science, an educated guess is called an _____.
a. question b. observation c. hypothesis d. conclusion
3. The process of obtaining information by using the senses is called a/an _____.
a. observation b. inquiry c. conclusion d. scientific investigation
4. A scientific procedure undertaken to make a discovery, test a hypothesis, or
demonstrate a known fact is a/an _____.
a. law b. hypothesis c. theory d. experiment
5. When you decide whether or not the findings support the original hypothesis, you
are _____.
a. making observations c. drawing conclusions
b. asking questions d. drawing a hypothesis

22. Controlling
Variables in a
Scientific
Investigation

23. Now, answer the following questions:
1. For his experiment, why did Anthony buy the same kind of fish as those that had died? Could he not have used
just any kind of aquarium fish?
2. Why did Anthony keep the fish he had bought in the aquarium for two days before starting his investigation?
3. Why did he use two jars of the same size, put the same amount of water in the jars and place the same number
and kind of fish in each jar? Was it necessary that the conditions in the two jars be the same at the beginning of the
experiment?
Why or why not?
4. Why did Anthony put ice cubes in only one jar? Why not in both jars?
Illustrate the 2 set-ups used in the experiment:

24. The conditions in the jars are called
VARIABLES. Variables are elements or a
particular aspect of an experiment that
may be changed. There are two types of
VARIABLE, namely: INDEPENDENT
VARIABLE and the DEPENDENT VARIABLE

25. 1. Manipulated variables or
independent variable is a
factor or condition that is
intentionally changed by
an investigator in an
experiment. An
independent variable is
the cause. Its value is
independent of other
variables in your study.
2. A responding or
dependent variable is a
factor or condition that
might be affected as a
result of that change. A
dependent variable is
the effect. Its value
depends on changes in
the independent
variable.

26. The variables in Anthony’s experiment include the temperature
of the water, the type of fish, the pebbles, aquarium plants, the
size of the jar, etc.
Anthony wanted to test the effect of the sudden change in
temperature in the fish. This means that in this particular
experiment,
the independent variable is the temperature of the water (which
is what we changed) and the dependent variable is the fish
(which died in response to the change in the temperature of the
water).

29. Controlling
Variables in a
Scientific
Investigation

30. The things that are changing in an experiment or
scientific investigation are called variables. A
variable is any factor, trait, or condition that can
exist in differing amounts or types. An experiment
usually has three kinds of variables: independent,
dependent and controlled.

31. 3. A variable that is not changed is called a controlled
variable. These factors are kept constant to
determine any changes in the results (dependent
variable) is caused by the manipulated variable.

33. he 2 set-ups used in the experiment:
JAR NUMBER 1 JAR NUMBER 2

34. The two jars that Anthony prepared are called the SET-UPS. There are two
types of set-ups, namely: CONTROL SET-UP and EXPERIMENTAL SET-UP.
The experimental set-up is the set-up where one variable has been
changed, whereas the control set-up is identical to the experimental set-
up except that no variable has been changed. The purpose of the control
set-up is for comparison and reference.
Anthony’s Jar no. 1 is the experimental set-up because it is where
he made changes to one variable. He put ice cubes in it to change the
temperature of the water. Jar no. 2 is the control set-up because no
changes has been done to it. Its purpose is for Anthony to compare and
come up with the conclusion that it is the sudden change in temperature
of the water that caused the fish to die.

36. I. Multiple Choice: Read each item carefully and encircle the letter of your answer.
1. In an experiment, the one variable that is changed is called _____.
a. independent variable c. experimental variable
b. dependent variable d. controlled variable
2. In an experiment, the factor that we measure is called _____.
a. independent variable c. experimental variable
b. dependent variable d. controlled variable
3. What is the only difference between the control group and the experimental groups in a controlled experiment?
a. the test b. the prediction c. the variable d. the hypothesis
4. A scientist hypothesizes that the temperature at which an alligator’s egg is incubated will
determine whether the alligator will be male or female. The independent variable is _____.
a. the incubator c. the gender of the alligator
b. the male alligators d. the temperature
5. A scientist hypothesizes that the temperature at which an alligator’s egg is incubated will
determine whether the alligator will be male or female. The independent variable is _____.
a. the incubator c. the temperature
b. the size of the baby alligators d. the gender of the baby alligators

37. What a Bright Idea!
Anton came from a poor family. Oftentimes, he goes to school
without having any breakfast at all. He strives to study hard and
sells sampaguita before going to school and salted egg at night.
For him, poverty is a motivation to work harder for his dreams.
He also buys scrap and recyclable materials and sells them in
the junk shop every weekends.
A science project in class changed his life. The teacher asked
them to create a science project which can be of help to their
neighborhood. At first, Anton got no idea on what to do. He does
not even have enough money to start and buy his materials. He
went home unhappily. It was about to rain and the house was so
dark since they do not have electricity at home. He stared at the
roof, sighed and said, “If only I can make this house brighter at
no cost”.

38. That weekend, he noticed many plastic
bottles in a junkyard. He thought of an
idea, “What can I make out of these
bottles?” He gathered soda bottle, filled it
with purified water and mixed with two
caps of bleach then juts this half-way up
the roof. The sun's light is refracted by the
water, casting a glow from above. This
brought lightings to his home. He got the
highest score in his project. He also
introduced this to his neighbors and they
gave him money for every improvised lamp
he prepares for them.

39. Guide Questions:
1. How did Anton conduct scientific investigation?
_______________________________
_______________________________
_______________________________
2. What steps did he perform or follow to solve his
problems?
_______________________________
_______________________________
_______________________________

40. Niko Tinbergen (1907-1988) was a Swedish
Ethologist (animal behaviorist) famous for studying
animals in their native habitats. One of his classic
experiments involved a bird called the black-headed
gull (Larus ridibundus). Black-headed gulls build
nests of twigs on the ground and lay light brown
eggs that are covered with dark brown spots.
However, the inside of the egg is white in color.
Tinbergen noticed that adult gulls pick up the
eggshells shortly after a chick has hatched, and fly
them to a location far from the nest, where they are
left. Since this behavior required expending energy
and time that could have been spent feeding and
protecting the chicks, Tinbergen wanted to know
why the birds did this.

41. Problem: Why do black-headed gulls remove eggshells from the
nest?
Hypothesis: The white interior of the shell is not camouflaged
and attracts predators to the nest. Therefore, the gulls remove
the shells to decrease predation.
Test: Tinbergen and his co-workers collected gull eggs and
painted 69 of them white and left 68 of them with their natural
color. (Statistically, these numbers are close enough to be
considered equal.)
The researchers then scattered the eggs next to a gull breeding
area and observed from a nearby blind. Predation rates were
recorded for white versus natural colored eggs.

42. a. Do the results of this experiment support the hypothesis? Why or
why not?
b. If you were working with Tinbergen, what would you suggest be
done next?
c. Identify the independent variables in the article.
d. Identify the dependent variables in the article.

44. Activity 2. Sci-Steps in Line
Directions: Read the situation below then answer or perform
the activity that follows.
Andrew, a baker in his town, is making pandesal. He had
some problems in the start but in the end, solved them
patiently. The following were the steps he conducted. Match
the steps in scientific method from column A with Andrew’s
works in Column B, Write the letter of your answer on the
space provided before the number.

45. Column A
_____1. Observe and
define the problem or ask
questions
_____2. Make a
hypothesis (educated
guess
_____3. Test the
hypothesis
_____4. Make a
conclusion or generalization
Column B
A. He prepared all his ingredients. Mixed
them up. Add more water and put them
in the oven. He got better results. The
pandesal is no longer lumpy.
B. Andrew, after seeing that the
pandesal was lumpy, asked himself,
“What could have caused this?”
C. He then realized that the lumpiness
of pandesal means it requires more
water
D. He thought, “If I add more water, the
pandesal may no longer be lumpy”

47. THANK YOUUU <3