1. Science
The Parts of an
Experiment

2. In this lesson we will continue our study into
“The Nature of Science”
and look at the different parts of an experiment.

3. Take Notes on this page Notes Elements of an Experiment Word
Name: __________________________ Period: ____
Elements of an Experiment
Word
Definition
Independent Variable
Dependent Variable
Control
Constant
Quantitative
Qualitative
Take Notes on this page
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
Independent Variable: (What did he change?)
Dependent Variable: (What did he measure?)
Control: (What did he compare it to?)
Constants: (What did he have to keep the same?)
Was the data qualitative or quantitative?

4. The part of the experiment you change on purpose IV = I Change
Word Definition
Independent Variable (IV)
The part of the experiment you change on purpose IV = I Change

5. The part of the experiment you measure.
Word Definition
Dependent Variable (DV)
The part of the experiment you measure.

6. Word Definition
Control
The original part of the experiment that is used for comparison. (NORMAL group)
Water is the picture here because during experiments with different liquids on plants, water on the plants would be the control group.

7. The part of the experiment that stays the same in every experiment
Word Definition
Constant
The part of the experiment that stays the same in every experiment
The picture shows the same type of dish used in all three experiments.

8. Word Definition
Quantitative
Data that is measured and collected with NUMBERS (length, mass, # of plants, etc.)

9. Word Definition
Qualitative
Data that is measured with words and descriptions (how smooth, what color, etc.)
Picture shows colors, a type of qualitative data.

10. WITH YOUR TEACHER BEFORE GOING ON !
STOP
HERE
YOU NEED TO CHECK IN
WITH YOUR TEACHER BEFORE GOING ON !

11. Practice Problem
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
What is the (IV) Independent Variable? What is being changed on purpose?
The type of soil (sand, soil, etc…)

12. Practice Problem
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
What is the DV Dependent Variable?
What is being measured?
Height of the Plants

13. Practice Problem What is the Control?
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
What is the Control?
What is the normal condition or comparison group?
Plants grown in regular soil

14. Practice Problem What are some constants?
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
What are some constants?
What conditions need to stay the same?
Type of plant (corn), amount of water the plants receive, amount of sunlight

15. Practice Problem Is the data quantitative (numbers) Or
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
Is the data
quantitative (numbers) Or
qualitative (words)
Quantitative (numbers, plant height)

16. Finding the parts of an experiment we just discussed
Now it is your
Turn to practice
Finding the parts of an experiment we just discussed

17. Experiments and Variables Worksheet
Name: ___________________________ Period: _____
Experiments and Variables Worksheet 1.
A superhero wants to investigate what cape material would help her fly faster. She measures how fast she can fly three miles while wearing a silk cape, a wool cape, a cotton cape, and her regular spandex cape.
Independent Variable: (What did she change?)
Dependent Variable: (What did she measure?)
Control: (What did she compare it to?)
Constants: (What did she have to keep same?)
Was the data qualitative or quantitative? 2.
A spy wants to test if juices
work better as invisible ink than what he bought at the store. He asks 8 people to read messages written using his normal ink, lemon juice, lime juice, & apple juice. He counted how many words they could read correctly.
Independent Variable: (What did he change?)
Dependent Variable: (What did he measure?)
Control: (What did he compare it to?)
Constants: (What did he have to keep same?)
Was the data qualitative or quantitative? 3.
Sally decided to test if
other breads mold faster
than her mom’s homemade bread. She put out 4 types (her mom’s, white, wheat, and rye). She checked them every day for 2 weeks and recorded the day when the mold first appeared.
Independent Variable: (What did he change?)
Dependent Variable: (What did he measure?)
Control: (What did he compare it to?)
Constants: (What did he have to keep same?)
Was the data qualitative or quantitative?

18. Lulu wondered if robots with different-shaped 4.
Lulu wondered if robots
with different-shaped
heads could figure out a maze differently. He first robot had a square head. Then she built 3 identical robots, but made their heads different shapes (round, oval, and heart). She timed how fast each robot could complete a complex maze.
Independent Variable: (What did she change?)
Dependent Variable: (What did she measure?)
Control: (What did she compare it to?)
Constants: (What did she have to keep same?)
Was the data qualitative or quantitative? 5.
A certain superhero
wanted to find out what material made his shield fly the farthest. He made his original out of plastic. Then made two more shields out of different materials (steel and polycarbonate). He then threw them and measured how far they flew.
Independent Variable: (What did she change?)
Dependent Variable: (What did she measure?)
Control: (What did she compare it to?)
Constants: (What did she have to keep same?)
Was the data qualitative or quantitative? 6.
A lifeguard wanted to know what sunscreen protects the best. He measured out 4 spots on his arm and applied a different sunscreen to each. He put his arm in the sun for 45 minutes. He compared each square.
Independent Variable: (What did he change?)
Dependent Variable: (What did he measure?)
Control: (What did he compare it to?)
Constants: (What did he have to keep same?)
Was the data qualitative or quantitative?

19. WITH YOUR TEACHER BEFORE GOING ON !
STOP
HERE
YOU NEED TO CHECK IN
WITH YOUR TEACHER BEFORE GOING ON !

20. Answer Key: Elements of an Experiment Word Definition
Name: __________________________ Period: ____
Elements of an Experiment
Word
Definition
Independent Variable
The part of the experiment you change
Dependent Variable
The part of the experiment you measure.
Control
The original
part of the experiment that is used for comparison. (NORMAL group)
Constant
The part of the experiment that stays the same in every experiment.
Quantitative
Data that is measured with NUMBERS (length, mass, # of plants, etc.)
Qualitative
Data that is measured with descriptions (how smooth, what color, etc.)
A farmer wanted to see if sand helped his corn grow taller. He grew a crop of corn on regular soil, a crop on soil mixed with sand, and a crop on plain sand. At the end of the harvest, he measured the height of the plants.
Independent Variable: (What did he change?)
The soil
Dependent Variable: (What did he measure?)
The height of the plants
Control: (What did he compare it to?)
The regular soil
Constants: (What did he have to keep the same?)
The water, sunlight, plant.
Was the data qualitative or quantitative?
Quantitative

21. Homework
Complete any 3

22. Homework
Complete any 3

23. WITH YOUR TEACHER BEFORE GOING ON !
STOP
HERE
YOU NEED TO CHECK IN
WITH YOUR TEACHER BEFORE GOING ON !

24. Experiments and Variables Worksheet – Answer Key
Name:
Experiments and Variables Worksheet – Answer Key 1.
A superhero wants to investigate what cape material would help her fly faster. She measures how fast she can fly three miles while wearing a silk cape, a wool cape, a cotton cape, and her regular spandex cape.
Independent Variable: (What did she change?)
Cape Material
Dependent Variable: (What did she measure?)
How fast she can fly
Control: (What did she compare it to?)
Regular Spandex Cape
Constants: (What did she have to keep same?)
Size & shape of cape, Where she flew, Weather conditions
Was the data qualitative or quantitative? 2.
A spy wants to test if juices
work better as invisible ink than what he bought at the store. He asks 8 people to read messages written using his normal ink, lemon juice, lime juice, & apple juice. He counted how many words they could read correctly.
Independent Variable: (What did he change?)
Type of Liquid for Ink
Dependent Variable: (What did he measure?)
How Many Words They Read Correctly
Control: (What did he compare it to?)
Normal Ink
Constants: (What did he have to keep same?)
Message, People Reading, Amount of Ink Used
Was the data qualitative or quantitative? 3.
Sally decided to test if
other breads mold faster
than her mom’s homemade bread. She put out 4 types (her mom’s, white, wheat, and rye). She checked them every day for 2 weeks and recorded the day when the mold first appeared.
Independent Variable: (What did she change?)
Type of Bread
Dependent Variable: (What did she measure?)
The Day the Mold Appeared
Control: (What did she compare it to?)
Mom’s Bread
Constants: (What did she have to keep same?)
Location, Size & Thickness of Bread
Was the data qualitative or quantitative?

25. Lulu wondered if robots with different-shaped 4.
Lulu wondered if robots
with different-shaped
heads could figure out a maze differently. He first robot had a square head. Then she built 3 identical robots, but made their heads different shapes (round, oval, and heart). She timed how fast each robot could complete a complex maze.
Independent Variable: (What did she change?)
Shape of Head
Dependent Variable: (What did she measure?)
How Fast They Completed Maze
Control: (What did she compare it to?)
Square Head
Constants: (What did she have to keep same?)
Body of Robot, Wiring & Programming, Maze
Was the data qualitative or quantitative? 5.
A certain superhero
wanted to find out what material made his shield fly the farthest. He made his original out of plastic. Then made two more shields out of different materials (steel and polycarbonate). He then threw them and measured how far they flew.
Independent Variable: (What did he change?)
Material for Shield
Dependent Variable: (What did he measure?)
How Far They Flew
Control: (What did he compare it to?)
Regular Shield
Constants: (What did he have to keep same?)
Size & Shape, How Hard Threw Shields
Was the data qualitative or quantitative? 6.
A lifeguard wanted to know what sunscreen protects the best. He measured out 4 spots on his arm and applied a different sunscreen to each. He put his arm in the sun for 45 minutes. He compared each square.
Independent Variable: (What did he change?)
Type of Sunscreen
Dependent Variable: (What did he measure?)
How Sunburnt He Got
Control: (What did he compare it to?)
Skin with no Sunscreen
Constants: (What did he have to keep same?)
Type of Skin, When & How Long in Sun
Was the data qualitative or quantitative?
7. Why should experiments be repeated more than once? To make sure the results are the same every time.