The English ‘alphabet song’, also known as ‘The ABC’, is based on a tune by Mozart, which in turn is based on a French tune, ‘Ah, vous dirai-je, maman (Ah! Would I tell you, mother?)’, which popped up in 1761. A couple decades later, Mozart used this tune in his Twelve Variations on Ah, vous dirai-je, maman.
This same tune is also used as the basis for such children’s songs as Twinkle, Twinkle, Little Star and Baa, Baa, Black Sheep.
In non-English tunes, such songs as the German Christmas carol Morgen kommt der Weihnachtsmann and the Hungarian Christmas carol Hull a pelyhes fehér hó also use this same tune.
Around a half a century after Mozart composed his Twelve Variations on Ah, vous dirai-je, maman an American music publisher named Charles Bradlee adapted the tune to fit with the English alphabet ‘lyrics’ and copyrighted his ‘The ABC, a German air with variations for the flute with an easy accompaniment for the piano forte song in 1835.
In North America, classically ‘z’ is often pronounced ‘zee’ rather than ‘zed’. This has created something of a problem as the pronunciation of ‘z’ as ‘zee’ has started to spread, much to the chagrin of elementary school teachers the English speaking world over.
This has resulted in them often having to re-teach children the ‘correct’ pronunciation of ‘z’ as ‘zed’, with the children having previously learned the song and the letter the American English way from such shows as Sesame Street.
Naturally, kids are often resistant to this change owing to the fact that “tee, u, vee, w, x, y and zed.
Because of the problem at the end of the alphabet song with “zed” not really fitting, a variety of other endings have been created to accommodate this, such as this one — “tu-v, w-x, y and z[ed], Sugar on your bread, Eat it all up, Before you are dead.”