In this feature, adapted from Interactive NOVA: "Earth," students explore the relationship between oxygen concentration and the well-being of various organisms by simulating a change in oxygen levels and observing what happens.

Data from NASA satellites establishes a 40 year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earths surface. This animation shows the ozone layer blocking harmful UV radiation from the Earths surface. The hole in the ozone is seen in purple. The location, size, and shape of the polar vortex is derived from potential vorticity data, PV. The pv, shown in white at 550 degrees Kelvin, is an atmospheric regional event that isolates polar air from the air at lower latitudes, producing conditions favorable for wintertime polar ozone depletion. The animation shows that most of the low-temperature and chemically-perturbed region is confined within the polar vortex during the Antarctic winter.

Students are introduced to the respiratory system, the lungs and air. They learn about how the lungs and diaphragm work, how air pollution affects lungs and respiratory functions, some widespread respiratory problems, and how engineers help us stay healthy by designing machines and medicines that support respiratory health and function.

Breathing shows an underwater scene and asks the students to answer the question, How do the people, fish and turtle get the oxygen they need?

In this activity, students use a simple pH indicator to measure how much CO2 is produced during respiration, at rest and after exercising. They begin by comparing some common household solutions in order to determine the color change of the indicator. They review the concepts of pH and respiration and extend their knowledge to measuring the effectiveness of bioremediation in the environment.

Ozone is formed when high energy ultra-violet radiation from the sun breaks apart molecular oxygen. An oxygen atom then combines with an oxygen molecule producing a new molecule with three atoms of oxygen, ozone.

Students will know some of the general properties of oxygen, carbon dioxide and water vapor

In these videos adapted from the Journal of Chemical Education, observe how a material that is usually hard to ignite becomes very flammable when its particles are suspended in air.

This illustration from Biology by Kenneth R. Miller and Joseph Levine describes the steps of the electron transport chain, the second stage in the process of cellular respiration.

Students learn about the periodic table and how pervasive the elements are in our daily lives. After reviewing the table organization and facts about the first 20 elements, they play an element identification game. They also learn that engineers incorporate these elements into the design of new products and processes. Acting as computer and animation engineers, students creatively express their new knowledge by creating a superhero character based on of the elements they now know so well.

This lesson introduces students to the concepts of air pollution and technologies that have been developed by engineers to reduce air pollution. Students develop an understanding of visible air pollutants with an incomplete combustion demonstration, a "smog in a jar" demonstration, construction of simple particulate matter collectors and by exploring engineering roles related to air pollution. Next, students develop awareness and understanding of the daily air quality and trends in air quality using the Air Quality Index (AQI) listed in the newspaper. Finally, students build and observe a variety of simple models in order to develop an understanding of how engineers use these technologies to clean up and prevent air pollution.

In this video adapted from the National Science Center, observe a demonstration to discover how helium gas is inert and hydrogen gas is reactive.

IMAGE-HENA observes the oxygen ions, expelled from the Earths atmosphere by the solar wind, return to the polar regions via the magnetic field.

IMAGE-HENA observes the oxygen ions, expelled from the Earths atmosphere by the solar wind, return to the polar regions via the magnetic field.

Electrically charged oxygen atoms (green) are ejected into the magnetosphere due to heating in the ionosphere. The red thermometer displays the intensity of the solar wind (dynamic pressure) measured by the Geotail spacecraft. The yellow thermometer represents the source intensity or hydrogen counts as measured by IMAGE-LENA.

This illustration from Biology by Kenneth R. Miller and Joseph Levine describes the steps of the Krebs cycle, the critical first stage in the process of cellular respiration.

This video segment adapted from Interactive NOVA features evidence of life on Earth before the atmosphere contained a rich supply of oxygen.

" This course is an introduction to chemical oceanography. It describes reservoir models and residence time, major ion composition of seawater, inputs to and outputs from the ocean via rivers, the atmosphere, and the sea floor. Biogeochemical cycling within the oceanic water column and sediments, emphasizing the roles played by the formation, transport, and alteration of oceanic particles and the effects that these processes have on seawater composition. Cycles of carbon, nitrogen, phosphorus, oxygen, and sulfur. Uptake of anthropogenic carbon dioxide by the ocean. Material presented through lectures and student-led presentation and discussion of recent papers."

The purpose of the following series of activities is to help students visualize the dead zone and to provide them with dissolved oxygen (DO) data to analyze and interpret. Students will plot and analyze DO from the July 23-28, 1993, scientific cruise in the Gulf of Mexico. The activities are designed to engage the students individually, within a group and as a class to plot, observe, analyze and interpret several different spatial slices of the dead zone. In addition, these graphing activities can also be used to graph other variables such as salinity, density and temperature. The five graphing and mapping activities are described in order from simplest to most complex.