University of California
Ucmp: Introduction to the Echinoidea
This University of California Berkeley site provides a detailed overview of echinoids, including a focus on how well they fossilize.
Stanford University
Stanford University: Sea Urchins
A good overview from Stanford University of the structure and function of sea urchins. A useful place to start in your study of echinoderms.
Stanford University
Sea Urchin Images
Free, downloadable images on a variety of topics related to urchin development, anatomy and physiology. Useful for teaching, worksheets and reports.
Stanford University
Stanford University: Sea Urchin Natural History
Stanford University offers an excellent review of the biology and ecology of sea urchins. After reading the text, try the reproduction/survival game!