Lesson 62 of 84 · Fossils
Lesson⭐ 30 XPCaves and Sinkholes (Part 2)
Caves and Sinkholes (Part 2).
🎯 Your mission
Understand the idea. Then look for it everywhere.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
Sinkholes form when underground limestone dissolves, leaving a cavity that collapses. They are common in areas with karst topography where water slowly dissolves the bedrock.
Key Words
- earthquake
- volcano
- landform
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test rock hardness using Mohs scale: try scratching rocks with your fingernail, a penny, and a nail. Rank them from softest to hardest.
Compare the before and after states.
Write your conclusion: did the results match your hypothesis? What would you change next time?
Check Your Understanding
Question 1
1 of 3What causes ocean tides?
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
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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