Little Lab Coats

🛠️ Test and Improve Your Force Design 🛠️

Physical Science — Forces & Motion | Unit 1, Lesson 6 of 6

📚 Grade: 3rd Grade⏱️ Duration: 50–65 minutes⚡ Subject: Physical Science

🧪🔧

Engineers test, learn from evidence, and improve their designs.

📋 NGSS Standard:
3-PS2-1 — Plan and conduct an investigation to provide evidence of the effects of balanced and unbalanced forces on the motion of an object.

🎯 Learning Objective

Students will test and improve your Force Design, compare what changed, and explain what the results show.

💡 The Big Idea

Designing is not just building once. Engineers test, gather evidence, and improve their designs so they work better.

🔬 The Science

Science Snapshot

A design improves when students connect the test result to the force idea that caused it.

What is happening?

Testing a force-based design shows whether the chosen push, pull, or magnetic idea actually solves the problem. Improvement comes from seeing where the design worked and where the force setup needs adjustment.

Why it works that way

If the motion was too weak, the design may need less friction, a stronger push, or a shorter magnetic distance. If the motion was uncontrolled, the design may need barriers, guides, or a different force direction.

Look for this in the lesson

Students should use evidence from the test to guide one clear improvement. That connects engineering back to the force ideas from the unit.

Ask while you read: Which force-related change is most likely to make your design work better on the next test?

📦 Materials

Your magnetic game or tool from Lesson 5
Magnets and magnetic pieces
Tape, cardboard, string, scissors, extra supplies for redesign
Pencil
Printed Student Worksheet

🔬 Let's Get Started

Step 1 — Review the Goal (5 min)
Look back at your original design goal. What was your design supposed to do?

Step 2 — Test Version 1 (10 min)
Run your design at least two times and record what happened.

Step 3 — Choose One Improvement (10 min)
Use your evidence to decide on one or two changes that should help the design work better.

Step 4 — Build Version 2 (15 min)
Make the improvement and label your new version.

Step 5 — Compare Versions (10 min)
Test version 2. Did the design improve? Use evidence to explain your answer.

💬 Discussion Questions

🗣️ Question 1: What problem did your first design have?Look for: a specific issue, such as weak magnet pull, pieces falling, or unclear rules.

🗣️ Question 2: What evidence helped you choose your redesign?Look for: observations from testing, not just guesses.

🗣️ Question 3: Did version 2 work better? How do you know?Look for: a comparison between the first and second versions using evidence.

✨ Extensions

📣 Share It: Explain your redesign to a family member or classmate.
🎯 New Goal: Add a harder challenge or new rule to your design.
📝 Engineer Reflection: Write one sentence about how evidence helps engineers improve ideas.

👩‍🏫 Parent/Teacher Notes

Normalize redesign: Improvement is a success, not a sign the first attempt failed.
Push evidence language: Ask what exactly happened during testing that led to the redesign.
Assessment check: Students should compare versions and support the comparison with evidence.

🛠️ Student Worksheet — Test and Improve Your Force Design 🛠️

Name: ________________________________ Date: ________________

Part 1 — Test Version 1

What happened when you tested your first design? __________________________________

What problem did you notice? __________________________________

Evidence from version 1: __________________________________

Part 2 — My Improvement

The change I made was __________________________________

I made this change because __________________________________

Part 3 — Compare Versions

Version 1 did __________________________________, but version 2 did __________________________________.

Version 2 worked better / the same / worse because __________________________________.

My proof is __________________________________.

Draw version 2 or label the improved part.

Draw here ✏️

🔑 Parent Answer Key

Detach note: This page is for parent/teacher reference. Student wording may vary.

Acceptable Responses

Students should identify a clear problem from testing.
The improvement should connect to that problem.
The comparison should use evidence from version 1 and version 2.
Strong responses name what version 1 did, what changed in version 2, and what proof shows whether version 2 was better, worse, or the same.

What Success Looks Like

Student uses evidence to justify the redesign.
Student can compare two versions clearly.
Student sees redesign as part of engineering.

Troubleshooting / Misconceptions

If version 2 still does not work well, that is still useful evidence.
If students choose random changes, ask them to connect the change to a specific problem from testing.