Changing melody and tempo songs

Scenes From an Italian Restaurant - Billy Joel

Suite Judy Blue Eyes - Crosby Stills Nash

Uncle Albert / Admiral Halsey - Paul and Linda McCartney 

Tool "Lateralus"

Tool "Schism"

Paul McCartney " Uncle Albert / Admiral Halsey"

Wings "Band on the Run"

Beatles "Day in a Life"

The Who "Baba O'Riley"

Ike & Tina Turner "Proud Mary"

Dexy's Midnight Runners "Come on Eileen"

Yes "I've Seen All Good People"

Elton John "Burn Down The Mission"

I know what you mean by changing tempo (though a song can change from 4/4 time to 3/4 time and still remain at the same tempo. Tempo refers to beats per minute), but what do you mean by changing melody?

In the classic Pop song construct, there is the melody of the verses, a different melodic line in the choruses, and in many older songs (though not all) a third section, called the bridge (in the U.S.A.) or middle-8 (in England), again with its own melody

So any song with both verses (all songs) and choruses (many, but not all) there is a change in melody. Are you asking for songs with two different verse sections, each with its own melody, different from the other?

Interesting question, one I'll have to think about. Not that many, I have a feeling.