Engineering Design Challenges — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A boat sank because it was too heavy. What should the team change first?
A) Use lighter materials
B) Add more weight
C) Make boat smaller
D) Test in a smaller pool
Lighter materials reduce overall weight so the boat floats above the water surface.
2. A catapult only flings 1 meter. The constraint says any rubber bands. Best fix?
A) Switch to string
B) Add stronger rubber bands
C) Remove the bands
D) Make it heavier
Stronger rubber bands store more elastic energy, which sends projectiles further away.
3. Time limit drops from 30 to 15 minutes. Which step might the team skip?
A) Brainstorming
B) Building
C) Detailed sketching
D) Testing
Detailed sketching can be shortened so the team still builds and tests on time.
4. After 3 trials, a marble run keeps stopping. What is most likely wrong?
A) Marble is too heavy
B) Track is too steep
C) Marble has wings
D) Track slope is too low
Low slopes give marbles too little gravity pull, so friction stops them quickly.
Part B: Fill in the Blank
Write the correct answer on each line.
1. When the budget drops, engineers must use cheaper or recycled materials instead.
Recycled items are usually free, helping teams stay under tight money limits.
2. If a team runs out of time, they should focus first on the essential steps only.
Essential steps deliver the working prototype, while extras can wait until later.
3. When a design fails, engineers ask why and use evidence to make a claim.
Claims explain results clearly and guide the next improvement based on real evidence.
4. If wind keeps knocking a tower, adding a wider base makes it more stable.
Wider bases lower the center of gravity so wind cannot tip the tower over easily.
5. Adding a new rule mid-project is called a constraint change that shifts the plan.
Constraint changes force teams to rethink materials, time, or methods quickly.