Information used for completion of coursework does not often need to be scholarly/peer-reviewed unless
specified by your instructor. For example, your instructor may direct you to use a certain number of resources for an assignment, of which some are required to be scholarly (e.g. cite at least 5 resources; 2 must be peer-reviewed). Scholarly articles are peer-reviewed, but there is a myriad of authoritative information available through resources such as databases, books/eBooks, encyclopedias, magazines, newspapers, and websites.
Scholarly is upper-level research material, but authoritative means that it is credible and may be utilized for academic coursework.
Examples
Scholarly: A peer-reviewed article from a medical journal such as the Journal of the American Medical Association (JAMA) or a science journal such as Research in Microbiology.
Authoritative: A book/eBook, such as The Civil War: Fort Sumter to Perryville by Shelby Foote, a database such as ProQuest One Literature, a magazine such as Sky and Telescope, a newspaper such as The New York Times, or a website such as NASA.gov.
All scholarly information is authoritative, but not all authoritative information is scholarly, by definition. Either or both are acceptable for academic use.