This is a lesson I made at the beginning of my first year of teaching that was a hot mess! I modified it to make it more focused and objective driven. It really is only helpful to you if you have a textbook that describes the KKK as a vigilante group, as they do in The Americans: Reconstruction to the 21st Century. Students corroborate two secondary source documents and try to figure out why authors who are writing about the same thing can have such different things to say.
Note: DAP stands for Date, Author, Purpose - the basics of sourcing (and also slang for a type of handshake!)