Independent and Dependent Variables

1. 1. Sara wants to see if a new brand of hair dye lasts longer than the brand she currently uses. She puts the new hair dye on the left side of her head and the old brand on the right. After 2 weeks, she observes which side of her head has more gray hair showing through.

What is the DEPENDENT VARIABLE?

• A. Brand of hair dye

• B. Number of grey hairs

2. 2. Rob is in charge of waxing the floor at the local mall. He wants to test a new brand of floor wax called Squeaky Clean. Rob waxes 20 floor tiles with Squeaky Clean and 20 tiles with the original wax brand. After one week, he counts the number of scratches on the floor.

What is the INDEPENDENT VARIABLE?

• 1. 1. Brand of floor wax

• 2. 2. Number of floor scratches

3. 3. Chris wants to see if his basil plants grow better in full sunlight or partial sunlight. He plants 5 basil plants on the east side of his house, which receives light only in the morning, and 5 more on the south side of his house, which receives light all day. After a month, Chris measures the height of each plant.

What is the DEPENDENT VARIABLE?

• C. Height of the plant

• D. Location of basil plants

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

4. 4. Shannon wants to see if the amount of time she studies will affect her grades. She normally studies for 30 minutes a night, but decides to double her study time to one hour per night. Over the next three weeks, Shannon sees her science grade raise 10%.

What is the INDEPENDENT VARIABLE?

• 3. 3. Amount of study time

• 4. 4. Science grade

5. 5. Eric wants to see if a Shark vacuum works better than his current Oreck. He makes sure both of the vacuum canisters are empty, and then vacuums half of the living room with the Oreck and the other half with the Shark. After vacuuming, he measures the amount of dust in each canister.

What is the DEPENDENT VARIABLE?

• E. Amount of dust

• F. Type of vacuum

Tags

NGSS.MS-ETS1-3

6. 6. Rebecca wants to see if her kitten prefers new chicken-flavored treats over her usual beef-flavored treats. She puts 10 chicken treats in one bowl and 10 beef-flavored treats in another bowl. She sees which treats her kitten eats first and repeats this experiment for 3 days.

What is the INDEPENDENT VARIABLE?

• 5. 5. Which treats the kitten eats first

• 6. 6. Flavor of treats

7. 7. Mark notices he has dropped calls on his cell phone when he walks into his bedroom. His friend told him to try wrapping aluminum foil around his phone to get a better signal. Mark talks on the phone 3 times while walking into his bedroom and drops 2 of the 3 calls. He wraps his phone in aluminum foil and talks on the phone 3 more times while walking into his bedroom. With the aluminum foil on his phone, he only drops 1 phone call.

What is the DEPENDENT VARIABLE?

• G. Number of dropped calls

• H. Wrapping the phone in foil

Tags

NGSS.MS-ETS1-1

NGSS.MS-ETS1-2

8. 8. Ruthie has a pet goldfish. After several months, the goldfish quits growing. Ruthie’s Mom told her the goldfish might have stopped growing because the tank is too small. Ruthie measures the size of her goldfish in its current tank and then puts the goldfish in a larger tank. After 2 months, the goldfish is now 1cm longer.

What is the INDEPENDENT VARIABLE?

• 7. 7. Size of the fish tank

• 8. 8. Length of the goldfish

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

NGSS.MS-LS2-4

9. Nicholas has been biting his nails since he was a kid. He wants to break the habit, so he puts bitter-tasting nail polish on his left hand and leaves his right hand without polish. After 3 days, he noticed his nails on his left hand had grown, but he continued to bite his right hand nails.

What is the DEPENDENT VARIABLE?

• I. Bitter tasting nail polish on the left hand.

• J. Length of fingernails

Tags

NGSS.MS-LS1-5

10. Pea plant clones are given different amounts of water for a three-week period. A pea plant receives 400 milliliters a day. The second pea plant receives 200 milliliters a day. The third pea plant receives 100 milliliters a day. The fourth pea plant does not receive any extra water; the plant only receives natural ways of receiving water. The height of pea plants is recorded daily.

What is the NDEPENDENT VARIABLE?

• 9. 9. Amount of water

• 10. 10. Height of pea plant

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1