Mark at mjanello@umich.edu couldn't finish the poem.
"p.s.  somebody finish this one, I'm stuck:"

Rusty VanBondo submits:

Jack and Jill went up the hill
to park the Karmann-Ghia,
On the E-brake the garter got stuck,
Jack couldn't free her.
Jack and Jill are still on the hill,
and Jack turned into Lil' Boy Blue.