Two simple experiments/demonstrations show the role of plants in mitigating the acidification caused when CO2 is dissolved in water.

This interactive exposes students to Earth's atmospheric gases of oxygen, carbon dioxide, and ozone. As the user manipulates the interactive to increase or decrease the concentration of each gas, explanations and images are provided that explain and visualize what the Earth would be like in each scenario.

This video documents how scientists, using marine algae, can study climate change in the past to help understand potential effects of climate change in the future.

This activity covers the role that the oceans may play in climate change and how climate change may affect the oceans. It is lesson 8 in a nine-lesson module Visualizing and Understanding the Science of Climate Change.

This lesson covers different aspects of the major greenhouse gases - water vapor, carbon dioxide, methane, nitrous oxides and CFCs - including some of the ways in which human activities are affecting the atmospheric concentrations of these key greenhouse gases. This is lesson six in a nine-lesson module about climate change.

In this experiment, students investigate the importance of carbon dioxide to the reproductive growth of a marine microalga, Dunalliela sp. (Note that the directions are for teachers and that students protocol sheets will need to be created by teachers.)

In this activity, students learn the basics of photosynthesis and respiration within the carbon cycle. Students are assigned to be different atoms or energy and interact with each other by linking together to form molecules and absorb or release energy.

This interactive graphic outlines the carbon cycle, with clickable text boxes that explain and elaborate each component.

In this 3-part lab activity, students investigate how carbon moves through the global carbon cycle and study the effects of specific feedback loops on the carbon cycle.

This is a polar map of permafrost extent in the Northern Hemisphere. A sidebar explains how permafrost, as it forms and later thaws, serves as both a sink and source for carbon to the atmosphere. Related multimedia is a slideshow of permafrost scientists from U. of Alaska, Fairbanks, collecting permafrost data in the field.