Lesson plan

Carbon into shells and rocks

Show how carbon dioxide in the ocean is incorporated into animal shells and some rocks.
Science content
Biology: Food Webs, Ecosystems, Biomes (3, 4)
Earth/Space: Rock cycle, Earth Materials, Natural resources (5)
Earth/Space: Sustainable practices, Interconnectedness (2, 5, 7)
Activities in this lesson

The CO2 in the ocean becomes part of the shells of ocean animals, and is also made into rock.
Show the chemistry of carbonate precipitation into calcium carbonate.

Calcium carbonate, from dead shelled animals or from chemical precipitation, is the starting point for many 'carbonate' rocks, as they enter the rock cycle.
If available, show a rock that is made up of shells (e.g. limestone), or show images from a "limestone shells" google search.
These shells from dead animals that drop to the ocean floor are buried in layers and layers until they are compressed into sedimentary rock. (If available show sedimentary rock that is clearly layers of shells.)

The carbonate chemistry remains the same as rocks move from sedimentary to metamorphic to igneous rock. The mineral is the same.
Other rock families have their own mineral chemistry.
Test for carbonate rocks, to identify which rocks of a collection are carbonate rocks.


Lesson 3 of 6 of a series on the Carbon Cycle.
Good image of the whole carbon cycle at https://www.britannica.com/science/carbon-cycle

Grades taught
Gr 5
Gr 6