Sink Float Showdown Exit Ticket
Formative Assessment
Sink Float Showdown
Show what you know about relative density!
Student Name
Date
Class Section
1
The Floating Toy
A heavy plastic toy boat floats safely on top of the water in a swimming pool. What does this tell us about the density of the toy boat compared to the water?
A The toy boat is more dense than water.
B The toy boat is less dense than water.
C The toy boat has no density at all.
D The water has no density at all.
2
The Beaker Test
Water
A
B
Look at the beaker on the left. Fill in each blank space using either the words more dense or less dense.
Object A floats because it is
than water.
Object B sinks because it is
than water.
3
Draw & Decide
A metal coin and a dry cork are dropped into a tank of water. Draw where each object will end up in the tank, and label them. Then complete the statement below.
Draw Tank Here:
Water Line
Why does the cork float at the top?
Grade 4 Science • Relative Density Unit Think Like a Scientist!
Sink Float Showdown Answer Key
Teacher Resource
Sink Float Showdown Key
Scoring Guide & Student Misconceptions
1
The Floating Toy — Answer: B
A heavy plastic toy boat floats safely on top of the water in a swimming pool. What does this tell us about the density of the toy boat compared to the water?
A More dense than water.
B Less dense than water. (CORRECT)
2
The Beaker Test
A
B
Object A floats because it is less dense than water.
Object B sinks because it is more dense than water.
3
Draw & Decide
Expected Student Drawing:
Water Line
Cork
Coin
Expected Explanation:
Explanation must include:
- The cork is less dense than water.
- Water is more dense than the cork.
- The upward buoyant force keeps it floating.
Quick Grading & Intervention Tips
Common Misconceptions
"Heavy things sink!" Students may think the boat floats because it's "light" or the coin sinks because it's "heavy." Remind them that huge steel cruise ships float!
Scoring Rubric
- Q1 (3 pts): Correctly selected B (Less dense).
- Q2 (4 pts): 2 pts for A (less), 2 pts for B (more).
- Q3 (3 pts): 1 pt drawing, 2 pts explanation logic.
Grade 4 Science • Teacher Answer Key Answer Key & Teacher Guide
