Lesson 24 of 84 · Engineering and Design
Experiment⭐ 30 XP🛠️ Engineer ShopVariables in Experiments (Part 2)
Engineering and Design.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Constraints make you more creative, not less.
Mind = Blown
🌉 The Eiffel Tower can grow 6 inches taller in summer because metal expands when hot.
Make a hypothesis first
Before you test: how many tries until it works?
What You'll Learn
Variables in experiments include the independent variable (what you change), dependent variable (what you measure), and controlled variables (what you keep the same).
Key Words
- hypothesis
- variable
Materials Needed
- aluminum foil
- ruler
- markers
- popsicle sticks
- pennies
- plastic wrap
Safety First
- Do not look directly at the sun or bright lights.
Steps
Look at the vocabulary words and write a definition for each in your own words.
Build a water filter using a bottle, sand, gravel, cotton, and charcoal. Pour muddy water through and measure how clear the output is.
Watch carefully for any changes and note the time.
Create a data table to organize your measurements.
Check Your Understanding
Question 1
1 of 3What is a hypothesis?
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.
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