Invisible by Pete Hautman

Next door neighbors Doug and Andy had been friends since they were small. They could open their bedroom windows and talk to each other long into the night. They remained friends even when Andy became popular and the odd reclusive Doug was bullied at school and spent all his spare time adding on to a model train set up started by his grandpa made all of match sticks.

They shared a fascination with fire with serious consequences. We learn the truth about the past and the present little by little. Doug's take on things doesn't mesh with the adults' around him. He is in therapy. He is supposed to be taking pills. Hautman wraps up his stories too quickly but this is a decent read. It is chillingly possible.
JDW11/7/06