Grade 3 · Science · Unit 6 of 15
How Earth's Surface Changes
Mountains, rivers, glaciers and sudden events.
What your child practises
Slow and fast changes to Earth's surface, with Alberta examples such as glaciers and rivers. Many First Nations, Métis and Inuit communities hold knowledge about the land passed down over generations.
Alberta Curriculum learning outcome: 3ES1.1 · changes to Earth's surface over long and short times
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Slow changes and sudden changes both shape the land. Which pair is correct?
⏳- weathering is slow; a landslide is fast
- both are always fast
- weathering is fast; erosion never happens
- both are always slow
Show answer
weathering is slow; a landslide is fast
Hint: Weathering takes a long time; landslides happen quickly.
Question 2
Why might a stream have rounded, smooth pebbles?
🪨- water rolls them against each other for a long time
- they were made smooth in a factory
- they grew round
- they melted
Show answer
water rolls them against each other for a long time
Hint: Tumbling in water wears the edges off.
Question 3
Why can a river carry more soil after heavy rain?
🌧️- fast, deep water has more energy to move material
- rain turns soil into water
- the river stops
- soil floats away on its own
Show answer
fast, deep water has more energy to move material
Hint: Fast water picks up and carries more sediment.
Question 4
Which describes a lake drying out?
☀️- birds drink it all
- the lake moves away
- water turns to stone
- water evaporates faster than it comes in
Show answer
water evaporates faster than it comes in
Hint: Lakes can shrink in dry times.
Question 5
Glaciers are…
🧊- clouds
- fast rivers
- lakes of milk
- very thick, slow-moving sheets of ice
Show answer
very thick, slow-moving sheets of ice
Hint: Glaciers can carve valleys.
Question 6
Which of these can protect land from erosion?
🌿- plants with strong roots
- heavy rain
- bare soil
- strong wind
Show answer
plants with strong roots
Hint: Roots hold soil in place.