Mountain Building & Erosion
📋 What it is
Colliding plates push up mountains; wind, water and ice slowly wear them back down.
🗣️ Coach says
Mountains are a tug-of-war. Colliding plates crumple and lift the crust UPWARD, building mountains over millions of years. At the same time, erosion — wind, rain, rivers, glaciers — grinds them back DOWN. A mountain’s shape reflects the current score in that endless building-vs-wearing battle.
🧠 Memory hook
Plates collide → mountains UP. Erosion (wind/water/ice) wears them DOWN. A never-ending tug-of-war.
😂 Giggle
What did the seismograph say to the earthquake?
"You really move me!"
😲 Whoa!
The Appalachian Mountains were once as tall as the Himalayas — but they’re hundreds of millions of years older, so erosion has worn them down to gentle hills.
✅ Quick check: Why are very old mountains (like the Appalachians) lower and rounder than young ones?
Say your answer out loud first — then reveal.
Erosion has had far longer to wear them down; young mountains are still tall and jagged.
Erosion smooths and lowers mountains over time.
🧪 Try it! (2 minutes)
Compare jagged young peaks vs rounded old hills in photos — age (erosion) shapes them.