Unit Plan 7 (Grade 4 Science): Designing Collision Devices

Focus: Model, test, and refine devices (helmets, bumpers, padding) that manage collision impacts, using questions, predictions, and engineering design.

Grade Level: 4

Subject Area: Science (Physical Science — Energy & Motion; Engineering Design)

Total Unit Duration: 5 sessions (one week), 45–60 minutes per session

I. Introduction

In this unit, students become engineers who design collision devices to help manage energy changes when objects collide. Building on their understanding of collisions and energy from the previous unit, they design, build, and test simple models such as helmets, bumpers, or crash barriers for moving carts or falling objects. Students learn to use criteria and constraints, ask and refine questions, predict outcomes, and compare multiple designs based on how well they reduce impact and protect a “passenger” or object.

Essential Questions

• How can we design devices that help manage the energy in a collision and protect people or objects?
• What questions and predictions help us improve our collision device designs?
• How do criteria and constraints guide the engineering design process?
• How can testing and comparing multiple designs help us choose the best solution to a collision problem?

II. Objectives and Standards

Learning Objectives — Students will be able to:

1. Describe a collision problem (e.g., protecting an egg/passenger or slowing a cart) and identify basic criteria and constraints for a solution.
2. Ask questions and predict outcomes about how changing design features (materials, shape, thickness) might change energy transfer in collisions.
3. Generate and build at least two different collision device designs (e.g., bumper systems, padding, “helmet” for a small object).
4. Test and compare designs using simple data (did the object break? how far did it move? how hard did the impact look/sound?).
5. Use evidence from tests to decide which design works best and suggest improvements.

Standards Alignment — 4th Grade (NGSS-Aligned)

• 4-PS3-3 — Ask questions and predict outcomes about changes in energy that occur when objects collide.
• 3-5-ETS1-2 — Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.

Success Criteria — Student Language

• I can describe a collision problem and list what my design must do (criteria) and must follow (constraints).
• I can ask questions and predict how changing my design (materials, shape, thickness) might change what happens in a collision.
• I can create more than one design for a collision device and explain how they are different.
• I can use test results (what happened in the collision) to decide which design works better and how to improve it.
• I can explain how my device helps manage energy in a collision (e.g., spreads out the force, slows things down, adds padding).