IJR, a news site, has an article with "17 Newspaper Front Pages that Depict the Most Iconic Days in 20th Century History". They include the Titanic, VE Day, The first Atomic Bomb, JFK's assassination, 9/11 and more.
This could be a good resource for history and social studies classes to use.
Take a look.
Just an FYI to teachers - the site also covers political news and has sponsored links on the bottom that may not be appropriate for young students.