How can a wiki be used to educate?

Wikis are powerful tools for teaching because they do not require any physical presence in order to educate.

Features

long distance learning
teaching materials easily uploaded
both students and instructors can work on or off of the wiki
skills assessment: no more danger of cheating than in traditional assignments, i.e. term/research papers; take-home examinations.
vandalism can be minimized by restricting access to parts of the wiki or to certain functions. It can be virtually eliminated by ‘closing’ the wiki, that is, requiring registration and/or proof of identity for registration.
only need to verify users once; then user can sign in using a password to confirm identity.
images, scans and video can be uploaded to the wiki
students can work cooperatively or alone
work submitted by students can be evaluated easily