These criteria for evaluating websites also apply to evaluating books, journal articles, and more...
Authority
Who wrote the pages?
Is this person or organization qualified to share information about this topic?
What is the real purpose of the website?
What is the website domain?
Objectivity
Are all sides of the issue represented?
Does the website have a hidden agenda or one-sided message to convey?
Is the website really an advertisement in disguise?
Currency
When was the website produced?
Was the website updated recently?
Are there lots of dead links on the pages?
Coverage
Is the information cited correctly?
Do the links to other pages complement the topic or theme?