Randy Hagen, age 8, of Costa Mesa, California, for his question:

What makes a Mexican bean Jump?

A bean is a vegetable. And everybody knows that vegetables are not supposed to move around by themselves. It is against the rules for a sprightly bean to jump and frisk about. But those funny little Mexican beans do indeed hop and jump. Some¬times one of them even turns a summersault or a sort of cartwheel in the air. Then it plonks down and rests before the next merry hop. Actually, the little bean is not doing this jumping by itself. Without help, it would squat in one spot just like any other vegetable.

The bean gets its jumping power from a little grub that lives inside and uses the Mexican bean as both a house and a pantry. His life began when his mother laid eggs in a number of bean blossoms. Later the flowers faded and changed into beans. Each moth egg hatched into a grub and stayed right inside a bean. The bean grows, and so does the grub inside. Now and then the grub needs to exercise. It coils up and suddenly uncoils. Its springy setting up exercises jerk the bean and the bean has to hop from spot to spot.