Understanding Oceans

This lesson is appropriate for children ages 11 and up. Understanding Oceans has students model ocean acidification using LEGO® bricks as atoms. Students also learn more about pH and mercury biomagnification in food webs. Students first model how increasing levels of carbon dioxide in the air can alter chemical reactions in the ocean water. Several short activities explain what the pH numbers mean, make predictions for our ocean’s pH in the future, and provide suggestions for what students can do to slow down ocean acidification.

Download the Molecule Sets Overview or read the Rationale for using LEGO bricks as atoms.

Molecule Sets:

You can make your own Molecule Sets by visiting our webpage: Information for Edgerton Center Molecule Sets. We are no longer able to sell Molecule Sets. We recommend students work in pairs with 1 kit.

The following LEGO bricks are the minimum required per kit for the Understanding Oceans Lesson:

• 12 red 2x4 bricks
• 4 black 2x4 bricks
• 4 grey 2x4 bricks
• 1 green 2x4 brick
• 12 white 1x2 bricks

NOTE: "2x4" and "1x2" refer to the number of bumps on top of the LEGO bricks.

Understanding Oceans Mats:

Print all mats in color at 100% size on 11"x17" paper or in halves on 8.5"x11" paper. The Atom Key/Layout Mat is required for all Molecule Set lessons. The Toxic Mercury in Our Environment Mat is optional, and can be completed with or without the rest of the Understanding Oceans lesson. It must be printed in thirds on 8.5"x11" paper.

The following mats are the minimum required per kit for the Understanding Oceans Lesson:

• Atom Key/Layout Mat
• Normal Ocean Chemistry Mat
• Ocean Acidification Mat
• Oceans and the pH Scale Mat
• Toxic Mercury in Our Environment Mat

The overviews below should help to teach this lesson. Students should already be familiar with the concept of LEGO bricks as atoms, having completed one of the previous topics (Chemical Reactions, Photosynthesis, and/or Understanding Air). Instructors need to add their own age-appropriate information and sources about the effects of mercury toxicity and healthy dietary consumption of fish.

Lesson Part 1 Overview: 

Normal Ocean Chemistry Mat and Ocean Acidification Mat required

Lesson 1 is designed to help students learn how increases in the amount of carbon dioxide in the air can affect normal ocean chemistry.

• Students will first model a normal ocean to observe the chemical reactions that occur in the ocean.
• Next, the students will model the chemical reactions that produce ocean acidification. The initial number of carbon dioxide molecules in the air above the water will be increased to observe what happens. A greater number of carbon dioxide molecules will be absorbed by the ocean.
• The increased carbon dioxide in the water has consequences now. The increase in free H atoms can make it too difficult for sea creatures to build chalk for their shells.

Lesson Part 2 Overview:

Oceans and the pH Scale Mat required

Lesson 2 is designed with 4 short activities on one large mat, to be completed in order.

• In the first activity, students work with white LEGO bricks that represent H atoms. In this way, students begin to visualize that the ‘H’ in pH as referring to the number of free hydrogens. It is not necessary to have younger students relate the pH numbers to negative exponents, however the negative log scale is given in the small inset as way for a teacher point out the connection.
• Seeing the pH numbers range from 0 to 14 may be helpful for some students. The other activities on the mat have additional objectives-- such as making predictions for our ocean’s pH in the future, and providing some actions to help slow ocean acidification.

Lesson Part 3 Overview: (Optional)

Toxic Mercury in Our Environment Mat required

For convenience only, this Mercury mat is placed in with Ocean materials. Note: The science of mercury biomagnification has little to do with acidification.

• Mercury is a poison. This lesson focuses on how mercury moves through the environment and how the mercury may accumulate in the fish humans eat.
• Mercury sources contribute both to the levels of mercury in air and in water all around the planet.
• Microorganisms found in soil take elemental mercury and create methylmercury molecules.
• The biomagnification of methylmercury in fish modeled. This example provides a hands-on activity, reinforcing the concept of food chains in the ocean.

Watch the ASTA Science Teacher Symposium Talk by Kathleen Vandiver on the Atoms and Molecules set, with a focus on the Understanding Oceans lesson.

Massachusetts State Frameworks for grades 6-8, Earth and Space Sciences Strand: 2. Energy Resources in the Earth System:

Central Concepts: Energy resources are used to sustain human civilization. The amount and accessibility of these resources influence their use and their impact on the environment.

2.1 Recognize, describe, and compare renewable energy resources (e.g., solar, wind, water, biomass) and nonrenewable energy resources (e.g., fossil fuels, nuclear energy).

2.2 Describe the effects on the environment.

Next Generation Science Standards:

MS-ESS3.D.1: Human activities, such as the release of greenhouse gases from burning fossil fuels, are major factors in the current rise in Earth’s mean surface temperature (global warming). Reducing the level of climate change and reducing human vulnerability to whatever climate changes do occur depend on the understanding of climate science, engineering capabilities, and other kinds of knowledge, such as understanding of human behavior and on applying that knowledge wisely in decisions and activities.

MS-PS1.B.1: Substances react chemically in characteristic ways. In a chemical process, the atoms that make up the original substances are regrouped into different molecules, and these new substances have different properties from those of the reactants.