Drawn from the P.U.S.: how Charlotte Mason might have introduced aquatic ecosystems

Subject: Aquatic Ecosystems

Group: Science. Class III. Time: depends, can be split over two or three sessions.
Books used: The World Around You, by Gary Parker. The Usborne Living World Encyclopedia. Philip's Atlas of the Oceans. Optional: The Silent World, by J.Y. Cousteau and Frederic Dumas.

Objects.
I. To introduce the concept of aquatic (vs. terrestrial) ecosystems
II. To describe inland and marine ecosystems.
III. To notice the common thread of this chapter: how each system is designed to support life

Introduction: review terms such as ecosystem, biotic and abiotic factors.  Name and describe some terrestrial ecosystems (rainforest, grassland, etc.).
  
Section One:  Lakes and Ponds, particularly about seasonal turnover. This section in The World Around You is written rather briefly; I prefer "Lake Turnover, How it Works" by R. Karl.

Hands-on demonstration of water density, with hot and cold water plus food colouring:  Lake Turnover, from Science North.  Draw a page for your science notebook, noting how seasonal turnover helps to sustain life in lakes.

Final notes on this section: rivers as a mixture of ecosystems (life in a river depends on factors such as what's on the bottom).

Section Two:  Marine Ecosystems, i.e. Oceans.  Look at the Vertical Distribution illustration on page 86 of the Atlas of the Oceans, showing the different depth zones. Read pages 25-27 in Parker, on the same topic.  Look at pages 22-23 in the Living World Encyclopedia, "The ocean surface," and pages 26-27, "The depths of the ocean."  Narrate, creatively, graphically, or otherwise.

Section Three:  Read pages 27-28 in Parker. Use the illustrated pages in The Living World Encyclopedia to look at Coral Reefs, Shorelines, and Estuaries.  Narrate, noting especially how life is sustained in different parts of the ocean and in special systems such as estuaries.

Bonus reading:  Chapter 13, "Beyond the Barrier," in The Silent World.(about coral reefs)

Bonus field trip:  Take a fall trip to the pond.
  
Adapted from Class Notes, as printed in various Parents' Reviews.