Lesson plan

Rock Cycle

Move through the rock cycle doing activities for each stage.
Science content
Earth/Space: Rock cycle, Earth Materials, Natural resources (5)

Materials in the chosen activities. Plus a piece of (local) sedimentary rock e.g. sandstone, mudstone, ideally showing layers. Plus a piece of (local) igneous rock e.g. basalt for extrusive igneous and granite for intrusive igneous (with magnifiers). Plus, if available, some pretty metamorphic rock showing contrasting folded layers.


Draw mountains on the board and an ocean.

Students sit in a circle around an erosion activity demonstration.
Discuss, while adding to the drawing, how rocks are weathered and eroded, washing particles into the ocean.
The valley formed can be discussed, but end on the layers of sediment building up in layers on the 'ocean floor'.

Students model their own sediment layering with the first step of the sedimentary uplifting activity, stopping after students have made their layers in the tray. Note how the layers undulate - they are not straight, just like the sediment layers on the ocean floor. (Don't let students shake or dig in the tray.)
While they do this, circulate with a piece of sandstone and mudstone, to show the layers (and maybe plant fossils). Students can feel the graininess of the rock but see that it has been so compressed with the pressure of sediments adding above it, that the layers are welded into a solid piece of rock.

Referring to the rock cycle drawing, and adding to it, tell students that a couple of things can happen to these sedimentary layers.

They can be pushed back up to the surface of the earth as tectonic plates move together, to uplift into mountains (add arrow to drawing).
Students return to their sedimentary uplifting activity, to push up the sedimentary layers, and then circulate to draw the shapes seen in the folded layers.
Show students images of sedimentary rock formations, and recognize some of the same shapes.

Or sedimentary rocks can be pushed deeper into the earth, where they are compressed further into metamorphic rock (add to drawing). This rock can also be uplifted - show a piece of metamorphic rock with crinkled layers if available.
If metamorphic rocks are pushed even deeper towards the molten centre of the earth, they heat up enough to melt. Melted rock is called magma.

Some magma comes to the surface fast when a volcano erupts, and cools rapidly on the surface to extrusive igneous rock (add to drawing).
Show basalt, a local extrusive igneous rock.
Other magma moves more slowly upwards inside the earth so that it cools slowly to form intrusive igneous rock (add to drawing). As it cools, there is time for the different kinds of mineral molecules to organize together to make crystals.
Distribute local granite and magnifiers for a granite study, looking for colours and large crystals.

Show crystal formation with a student crystal painting.
As they work, circulate to help them find crystals and crystals forming, referring to the same process happening deep inside the earth during the formation of intrusive igneous rock. (Do not focus on the water evaporating to form these crystals, as this is not the purpose of the activity in the context of this lesson.)

Referring to the rock cycle drawing, review how all rocks eventually cycle back to the surface, from which they are weathered and erode to wash into the ocean again.
Discuss how many cycles there are in the drawing - there are several different cycles in the rock cycle.


This lesson used as Lesson 4 of 6 of a series on the Carbon Cycle: 'Rocks back to the Surface'
This is the slow cycle of carbon, as it moves through rocks
Good image of the whole carbon cycle at https://www.britannica.com/science/carbon-cycle

Grades taught
Gr 4
Gr 5
Gr 6