well it does but not that bad as when you make paper because to make paper that causes air pollution and water pollution.

This is commonly called littering.

The indicator is litmus paper. :)

They by themselves produce little or no pollution. The pollution comes from the manufacture of the blackboard and book. There may be chemicals in the blackboard and book that can leech out, but it is probably extremely small. I work in a paper mill and we monitor the pollution we produce from the paper making process very closely and we try very hard to minimize that pollution.

You write what causes air pollution (Humans), then write what it does... (Intoxicate out air)