Here's a couple I remember:
Beans, beans, the magical fruit.
The more you eat, the more you toot.
The more you toot, the better you feel.
Beans, beans at every meal.
Open your legs and let it SQUEEEEEEEEEAAAAL!!!

When my sister was in pre-school, she came home one day and loudly chanted the following:
Down by the ocean, down by the sea.
You broke a bottle and blamed it on me.
I told Ma, Ma told Pa,
You got a whippin' so HA HA HA!