Just the chorus for a start:

KIDDIES, DON'T LET YOUR GRANNIES SIGN UP TO BE JARHEADS

Kiddies, don't let your grammas sign up to be jarheads!
Don't let 'em play Rambo and drive them old hum vees.
Let em knit sweaters, and bake and stay comfy.
Kiddies, don't let your grammas sign up to be jarheads!
They're way underweight and they'll never shoot straight,
'Specially on days when they're grumpy.