James Frank Davis, age 9, of Cape Elizabeth, Maine, for his question:

How do they make chalk?

Colored crayons are made from certain greases and waxy materials. But genuine powdery chalk is something quite different. You may not believe this, but chalk is made from tiny seashells. These shells are too small for your eyes to see and it takes many, many of them to make a small piece of blackboard chalk. They were created by mini creatures who lived in the sea ages and ages ago.

These mini creatures have been given a lovely long name. They are called foraminifera    and zillions of them lived in the ancient seas. They made their shells from chalky material dissolved in the water. And when they died, their shells sank to the bottom and formed thick layers of chalky material. This material is cleaned, mixed with weak glue and molded to make sticks of blackboard chalk.