At Seventeen by Janis Ian is in C at 100 beats per minute and runs 3:10 across 35 bars. It uses 11 chords — C, Cmaj7, C6, Dm11, Dm7, A, G7, Eb, and a few more. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? At Seventeen guitar melody tab.