You've done your search in a database and found a list of articles. Or you have some book titles to consider. You now have to decide whether or not these potential sources help you accomplish your purpose. One way to do that is to see how you might use those sources in your research paper.
The BEAM model below might be helpful. As you examine your results ask yourself, does this source fall into one (or more) of the categories below?
More Details
Background Sources
Exhibit Sources
Argument Sources
Method Sources
Citation
Adapted from Beeghly LIbrary, Heidelberg University: http://libguides.heidelberg.edu/eval/beam#s-lg-box-2260491
Additional Sources:
Meredith Farkas, Meredith. “Good for What? Teaching Sources for Sustainable Lifelong Information Literacy." Presentation, Association of College and Research Libraries, Portland, OR, March 25-28, 2015. http://www.slideshare.net/meredithfarkas/good-for-what
Rubick. Kate. 2014. "Flashlight: Using Bizup's BEAM to Illuminate the Rhetoric of Research." Presentation at Library Instruction West 2014. http://pdxscholar.library.pdx.edu/liw_portland/Presentations/Material/10/
Rumble, Juliet, Carter. Toni and Noe, Nancy. 2015. "Teaching Students the 'How' and 'Why' of Source Evaluation: Pedagogies that Empower Communities of Learning and Scholarship." Presentation at 2015 LOEX Conference. http://www.loexconference.org/2015/presentations/rumblePresentation.pdf
Woodward, Kristin M. and Ganski, Kate L., “BEAM Lesson Plan” (2013). UWM Libraries Instructional Materials. Paper 1. http://dc.uwm.edu/lib_staff_files/1
BEAM originally developed by Joseph Bizup.
Bizup, Joseph. "BEAM: A Rhetorical Vocabulary for Teaching Research-Based Writing." Rhetoric Review 27, no. 1 (2008): 72-86. doi:10.1080/07350190701738858
An important step in evaluating a resource is determining if it is considered scholarly. This distinction will need to be made for books, as well as articles.
Finding information & sources generally isn't a problem for students - finding quality, reliable sources tends to be more of a challenge.
It's important for you to take the time to evaluate the sources you discover in the course of your research.
The C.R.A.P. Test is one way of evaluating information, by focusing on the Currency, Relevance, Authority & Purpose or Point-of-View.