This short tutorial from the Purdue University Libraries will reinforce the ability to evaluate sources that was introduced in the Searchpath tutorial.
CRAAP
Currency - Is the information timely?
Relevance - Is the information relevant to your research needs (your thesis statement).
Authority - Is this information from a reliable source?
Accuracy - Is this information reliable, truthful, and correct?
Purpose - For what reason does this information exist?
The CRAAP test is adapted from the Meriam Library at California State University Chico.