Science and Technology K–6 · Kindergarten
Does a ball bounce back as high as it was dropped
Physical World (NSW 2017); Science understanding, Physical sciences (ACARA v9)
The idea
A dropped ball never bounces back to the height it fell from, and a higher drop gives a higher bounce.
Safety card
Hazards
- Balls bouncing into faces
Controls
- Drop zone kept clear; one dropper at a time
Note
No chemicals or heat. Record the activity on the school's risk assessment (Primary School RiskAssess, Ecosolve Australia, riskassess.com.au).
What you need
- A tennis ball, a basketball and a foam ball
- A 2 m strip of paper taped to a wall, marked every 10 cm from the floor and labelled 0 to 200 cm
- A hard floor (not carpet) beside the wall
- Recording table: drop height, bounce height, three trials per row
How to do it
- Hold the tennis ball with its bottom level with the 100 cm mark. Let go without throwing.
- A partner crouches level with the strip and calls the mark the bottom of the ball reaches on the first bounce. Record it. Repeat three times.
- Repeat from 50 cm and from 150 cm (an adult does the 150 cm drop).
- Repeat the 100 cm drop with the basketball and the foam ball.
- Compare: is any bounce as high as the drop; which ball bounces highest; what happens when the drop is higher.
What you should see
No ball bounces back to its drop height; each bounce reaches a fraction of the drop height, and that fraction stays roughly the same for the same ball on the same floor, so a higher drop gives a higher bounce and doubling the drop height roughly doubles the bounce. The three balls reach different fractions; which ball bounces highest is read from the strip, not assumed. The learner knows it worked when all three trials at 100 cm land within about one 10 cm mark of each other.
What changes
- What you change
- drop height (50, 100, 150 cm); type of ball
- What you measure
- first bounce height (cm)
- What you keep the same
- same floor
- released, not thrown
- same observer position
- three trials
Common misconceptions
Each of these ideas is wrong, and the activity is a chance to test it.
- A ball can bounce higher than it was dropped if you drop it hard enough (dropping is not throwing).
- All balls bounce the same.
Curriculum references
The NSW syllabus outcomes and Australian Curriculum v9 codes this activity supports. They are references, not a verified or complete curriculum alignment.
- Science and Technology K-6 Syllabus (2017), NESA. Current syllabus; NESA's timeline is 2026 plan and prepare, 2027 start teaching the 2024 syllabus. Code read from the official syllabus document on 2026-09-22.STe-5PW-STSTe-1WS-S
- Science and Technology K-6 Syllabus (2024), NESA. Implementation from 2027, so this code describes the future syllabus. Code read from the outcomes page on 2026-09-22.STE-SCI-01STE-PQU-01
- Australian Curriculum v9AC9SFU02AC9SFI01AC9SFI02AC9SFI03AC9SFI04
Sources
The pages the author read to write this activity.