Here's the version my I learned from my Mom (she says she used to shock her Aunties with it when she was a kid):

Bang bang Lulu, Lulu's gone away
Who's gonna bang bang Lulu
Now that she's away?
Lulu had two boyfriends, both were very rich
One was the son of a banker
The other was a son of a
Beech nuts, beech nuts, five cents a pack
If you don't like them, I'll shove them up your
Ask me no questions, I'll tell you no more lies
A man got hit with a bag of (pause)
Right between the eyes.