Quick Changes, Slow Changes

Science · Volcanoes & Earthquakes · ages 5-7

Name ______________________ Date ____________

Which example shows a slow change to Earth's surface?
- Ground shifts during a short earthquake
- Water wears rock away over many years
- Lava covers a field within a few hours
Which example shows a quick change to Earth's surface?
- Lava covers ground in a few hours
- Wind wears rock away over many years
- Waves wear a cliff away over many years
An earthquake can shift or crack the ground in just a few seconds.
Circle one: True False
Which pair gives one quick change and one slow change?
- Lava covers land in hours; rock wears away over years
- Lava covers land in hours; ground shifts within seconds
- Rock wears away over years; a cliff shrinks over years
Sam wants to find out how long a cliff took to change. Which evidence would help most?
- One close picture of the smooth rock
- Dated photos taken over many years
- One list naming the cliff's colours
If water causes a change to land, the change must always be slow.
Circle one: True False
Yearly photos show a rocky hillside getting smaller bit by bit. Rain carries tiny pieces away each year. Which explanation fits?
- One earthquake changed it all in seconds
- One eruption covered it all within hours
- Water wore it away gradually over years
Leo hears that a volcano has been erupting for weeks. He says, 'It cannot be an eruption because eruptions end in one day.' Which reply checks his idea?
- Every eruption ends within one day
- Some eruptions keep going for longer
- Only the first day counts as an eruption

Answer key

For grown-ups. Fold this page away before handing over the rest.

Water wears rock away over many years · Rock wearing away little by little over many years is a slow change.
Lava covers ground in a few hours · A few hours is a short time compared with many years.
True · An earthquake can move the ground in seconds and cause a quick change.
Lava covers land in hours; rock wears away over years · Hours is a short time here, while gradual wearing over years is a long time. That pair has one of each.
Dated photos taken over many years · Dated photos show the cliff at different known times. A single view or colour list does not show how long the change took.
False · Water can wear rock away slowly, but a flood can wash soil away quickly.
Water wore it away gradually over years · Repeated loss of tiny pieces over years shows gradual wearing away by water.
Some eruptions keep going for longer · Some eruptions last for weeks or longer. A quick change during an eruption does not limit how long the whole eruption lasts.