Supernovas enrich succeeding generations of stars and solar systems with heavy elements Some 5 billion years from now, our Sun will gradually expand into a red giant. By then, perhaps, our space-faring descendants will have migrated to safety!

http://www.observe.ivv.nasa.gov/nasa/space/stellardeath/stellardeath_intro.html
Stellar Evolution and Death: life cycle of stars and additional information.

http://amazing-space.stsci.edu/light/stellarEncounters-frames.html
Amazing Space: an activity on identifying the temperature of stars based on color.