Is the author identified? Are author credentials listed? (Look at the end of the article or at the bottom of the first page.)
Check the date for currency. Is this important for your topic?
Look at the length of the article. Is it long enough to provide sufficient content?
What is the level of language: Easy enough for a child? Generally understood by an adult? Scholarly? Technical?
Is the information accurate? (Compare with other sources.) Are sources cited?
Does the article contain a list of references at the end?
What is the purpose of the article: To inform? Persuade? Entertain?
What type of publication is it: Scholarly? Professional or technical? General interest? Newspaper?
Does the publication that the article is in have a bias? Does it present different points of view? Editorials, op-ed pieces, and commentary will almost always present an opinion or bias, but other articles may, too.