PBS
Pbs: Evolution
This is the PBS Evolution site, including excellent information on Darwin, Change, Extinction, Survival, Sex, Humans, and Religion.
University of California
University of California Museum of Paleontology: Understanding Evolution
This resource presents extensive information for learning about and teaching evolution including an in depth course "Evolution 101", teaching materials, and a resource library.
University of California
University of California Museum of Paleontology: Homologies
These pages are from the Understanding Evolution website for teachers. They focus on homologous structures that organisms with common ancestors share.
New York University
Nyu: Darwin's Evidence for Evolution: Embryology
Concise description of embryology as evidence for evolution, as used by Darwin.
Other
The Evidence for Evolution
These pages are part of a site called "Evolution," that accompanies a textbook by the same name. Mark Ridley is the author, and in this section he discusses the evidence for evolution.