Duration
45 minutes plus discussion time and activitiesThis lesson is associated with the 2026 SeaWeek theme: 'Caring for Planet Water - The ocean makes the Earth habitable.'
Preparation
Background information for this lesson can be found in Caring for Planet Water PowerPoint – Teacher Resource Sheet
PowerPoint: Caring for Planet Water
Student Worksheet 1: Caring for Planet Water Glossary
Student Worksheet 2: Caring for Planet Water Crossword
Student Worksheet 3: Caring for Planet Water – Ocean Acidification Experiment
This lesson is centred around Ocean Literacy Principle 4: The ocean makes Earth habitable. Students will learn about how the ocean was a key part of how life on Earth began, and how the ocean continues to influence our lives.
Students will learn:
• How conditions in the ocean allowed life to develop on Earth billions of years ago
• How oxygen increased in the atmosphere, and which organisms were responsible
• That 50-80% of Earth’s oxygen production comes from the ocean
• Phytoplankton in the ocean is responsible for most of the ocean’s oxygen production
• The ocean is a carbon sink
• The ocean removes carbon via the biological pump, physical pump and carbonate pump
• Many marine organisms use calcium carbonate to create shells and internal skeletons
Stromatolites are some of the earliest forms of life on earth. They produce oxygen and can still be found on Earth today.