It Ain't Necessarily So by George Gershwin is in C at 100 beats per minute and runs 3:14 across 70 bars. It uses 30 chords — Am, Eb, D, Gm, C, N.C., C7, Db7, 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? It Ain't Necessarily So guitar melody tab.