A number of the news sources listed below will feature articles written through some sort of lens, or frame. Part of your assignment is to be able to identify that lens and any assumptions the writer may have in the article they have written.
The Pew Research Center has written a report on the polarization of the media based on political ideologies and might be an interesting read while you're working through the selection of news resources and your analysis: Political Polarization & Media Habits.
A journalist for Business Insider wrote a piece discussing the partisan news divide based on the aforementioned Pew Research Center report: Here's How Liberal Or Conservative Major News Sources Really Are.
These library databases will help you locate contemporary news for your news analysis by providing full-text news from many regional, national, and international newspapers.
Use these databases to search major national newspapers including the New York Times; the Washington Post; and the Wall Street Journal.