Ducksters
Ducksters: Chemistry for Kids: Radioactivity and Radiation
Kids learn about the science of radioactivity and radiation in chemistry including radioactive decay, types, measurements, half-life, and the dangers.
Idaho State University
Radioactivity in Nature
Interesting information including: average annual dosage, radioactivity in space, in the human body, and in the oceans.
PBS
Pbs Learning Media: The Dating Game: Radioactive Carbon
In this media-rich essay from the NOVA: "Mystery of the First Americans" Web site, learn about the atomic structure of radioactive carbon and how it can be used to determine the age of organic remains, such as bones and teeth.
US Geological Survey
The Numeric Time Scale
This is a good source for getting an in-depth description of using radioactive decay to measure the ages of rocks. In addition to describing the process of radiometric dating, this resource also includes a geologic time scale and four...
Ducksters
Ducksters: Chemistry for Kids: Isotopes
Study the science of isotopes in chemistry including naming isotopes, hydrogen, examples, fun facts, unstable, and stable on this site.