Forces | Project Based Learning
Students work in teams to design, build, test, and improve a device that protects an object from damage when dropped. Through this project, they investigate balanced and unbalanced forces, gravity, friction, and impact, and use evidence from testing to improve their design.
| Term | Definition |
|---|---|
| Force | A push or pull that can change the motion of an object. |
| Gravity | The force that pulls objects toward Earth. |
| Friction | A force that slows down motion when surfaces rub against each other. |
| Impact | The force that happens when objects collide or hit something. |
| Balanced forces | Equal forces acting on an object so its motion does not change. |
| Unbalanced forces | Unequal forces that cause an object to start moving, stop, speed up, or slow down. |
Show a small object being dropped and ask: How could we protect it from the force of impact? Introduce the challenge: design a landing device that keeps the object safe from a drop.
Observe, discuss ideas, and predict which materials might reduce damage.
Review the goal, rules, and available materials. Prompt teams to sketch a quick plan and identify which forces their design should reduce or redirect.
Work in teams to sketch a design and assign roles such as builder, tester, recorder, and materials manager.
Circulate, ask guiding questions, and support safe and focused construction. Remind students to think about cushioning, stability, and how the device will land.
Build the first prototype using selected materials.
Model a fair test procedure and drop height. Ask teams to test once, observe the result, and record evidence about whether the object was protected.
Test the device, measure results, and record observations about damage, bounce, or stability.
Prompt students to compare results and identify one design change based on evidence. Encourage use of science vocabulary in discussion.
Modify the prototype and retest if time allows, then compare the new result to the first test.
Invite each team to share what force their design addressed and what they changed after testing.
Briefly present their design, test results, and improvement ideas.
Students complete a one-sentence reflection: My design worked because ____. The force I tried to reduce was ____. Review that forces can change motion and that engineers improve designs by testing and revising.
Formative assessment will be based on teacher observation, team discussion, planning sketches, test records, and the final explanation of how the design reduced force. Use a simple rubric for understanding of forces, use of evidence, teamwork, and problem-solving.