Before You Accuse Me by Bo Diddley
"Before You Accuse Me" is usually the third song I teach to beginner guitar students because it uses a simple rhythmic shuffle pattern on two strings for each chord. The shuffle is easiest if it is played in the key of A (it is somewhat more difficult in the original key of E). In order to emphasize the repeating chord structure of the song, I sometimes call it "The ADAADDAAEDAA Song" with my students. The swing (triplet rhythm) shuffle pattern is commonly used in blues and (with a more even eighth-note rhythm) in rock and roll. It is easy to learn and sounds cool!
We also use this song for more advanced students to learn to improvise guitar solos using the A minor pentatonic scale.
The video above was made when some of my Group Guitar Lessons students played along with my band, Panther City Rounders. We played the song in A as we do in our lessons.
The video below is Bo Diddley's original recording in the key of E. There are many covers of the song by artists including Eric Clapton, Creedence Clearwater Revival, Delbert McClinton, and others - almost all of which are in the key of E.