In this online interactive English vocabulary skills worksheet, high schoolers answer 10 matching questions which require them to fill in the blanks in 10 sentences. Students may submit their answers to be scored.

In this "Deep Impact" quiz activity, students answer a set of multiple choice questions about the film. Students may click on an "answer button for immediate feedback.

Analyze nuclear fission chain reactions and how to prevent them as well as explore ways to control nuclear reactions through these simulations.

What happens when a nuclear reactor overheats? This video segment adapted from FRONTLINE looks at the nuclear reactor meltdown at Chernobyl, the worst accident of its kind.

Start a chain reaction, or introduce non-radioactive isotopes to prevent one. Control energy production in a nuclear reactor.

[Free Registration/Login Required] Learn about how radiocarbon dating works and how anthropologists can use this method to figure out who long ago people lived. A PDF worksheet and a video tutorial are also available. [5:41]

[Free Registration/Login Required] Study the basics of radioactive decay and the properties of atomic nuclei in Marie Curie's laboratory and classroom. A PDF worksheet and a video tutorial are also available. [3:32]