Answer Key
with target levels
Onions
EPC Strand C, Arrangements and movements
Level 3: Can explain why a volume of ice contains fewer molecules than the same volume of water.
Water molecules occupy more space when the water evaporates and they are moving more freely.
Level 2: Knows that a given volume of ice contains fewer molecules than the same volume of water.
Knows that in ice the spaces between the molecules are empty.
Level 1: Can describe the arrangements molecules in ice, water and water vapor. Can describe the movements of molecules in ice, water and water vapor. Knows that a given volume of water vapor contains fewer molecules than the same volume of liquid water.
Target level: EPC level 2a
A. Have you ever noticed that when people chop onions they look like they are crying?
In the space below, explain how you think a chemical from the onion could get into a person’s eye.
A chemical could get into a person’s eye by . . .
Mark and Kian are discussing what happens when they chop onions. They have two different ideas.
Target level: Argumentation 0b
B. What is Mark's idea about why people cry when they cut onions?
Mark's idea is that...
Target level: Argumentation 0b
C. What is Kian's idea about why people cry when they cut onions?
Kian's idea is that...
Target level: Argumentation 0d
Below, there are some pieces of evidence. Who does each piece of evidence support?
D2. A girl was cutting an onion, and her brother (who was on the other side of the table) started to cry too. This evidence supports...
A. Mark
B. Kian
C. Both
D. Neither
Target level: Argumentation 0d
D3. People only start crying after they cut the onion. This evidence supports...
A. Mark
B. Kian
C. Both
D. Neither
Target level: Argumentation 0d
D4. A student poured some of the onion liquid from the cutting board into a cup. She rubbed some in her eye, and she started to cry more.
A. Mark
B. Kian
C. Both
D. Neither
Target level: Argumentation 1c
E. “You said that evidence 2 supports [student]. Complete the last sentence below to form an argument. “A girl was cutting an onion, and her brother (who was on the other side of the table) started to cry too.” This evidence supports [student’s] idea because....”
Target level: none
After looking at ALL the evidence below (1-4), and thinking about what you know about cutting onions, which idea do you now agree with more?
Evidence:
1. Onions contain chemicals that are slightly irritating to humans.
2. A girl was cutting an onion, and her brother (who was on the other side of the table) started to cry too.
3. People only start crying after cutting the onion.
4. A student poured some of the onion liquid from the cutting board into a cup. She rubbed some in her eye and she started to cry more.
F. I agree more with...
A. Mark
B. Kian
Target level: Argumentation 2b
G. Why do you think [student’s] idea is better? Use evidence from below, your own knowledge of cutting onions, or both. I think [student’s] idea is better because...
Target level: Argumentation 2a
H. What do you think is wrong with [student’s] idea? I think the problem with [student’s] idea is...