Lesson 4 of 5 · Engineering and Design
Lesson⭐ 30 XP🛠️ Engineer ShopOptimising Against Several Criteria
Engineering and Design.
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ The twist
The first design always fails. That's the point.
Mind = Blown
🛠️ The first computer bug was a literal moth stuck inside a machine in 1947.
Make a hypothesis first
Guess: what's the weakest part of this build?
What You'll Learn
Real designs are judged on several criteria at once, and the best compromise depends on which matter most. Scoring each option against weighted criteria makes the reasoning visible instead of leaving it to instinct.
Key Words
Tap a word to see its definition.
Steps
Read the explanation above and note the two key terms before you start.
Build a decision matrix for three school-bag designs against cost, weight, durability and capacity. Score, weight and total them, then change the weightings and see whether the winner changes.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2A decision matrix makes design reasoning:
Where you see this in real life
Every bridge, building, and gadget you've ever used started with this.
Stretch Challenge
Try this in real life this week.
Find something that's broken at home and try to figure out *why* it broke.
For the dinner table
“What's something around the house you'd redesign — and how?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
Ready?
Optimising Against Several Criteria
Master the concept. Use it tomorrow.
Full screen — no distractions
Checkout complete lesson on Engineering and Design for 8th Grade
Get the full Engineering and Design track as a printable PDF — all lessons, worksheets, and answer keys.