I think that this thread is rapidly veering away from its original intent,
but coal certainly enters into memories of my elementry school days in Detroit.
In Holcomb Elementary School (dang, it is still there. The racial stats floor
me! :
http://schools.publicschoolsreport.com/Michigan/Detroit/HolcombElementarySchool.html  
) we had all of the same stuff, except you had to go downstairs to see the
boiler room.  Was your parking lot paved with coal ashes?

    True story: I was famous in my elementry school (unfairly so I think) as
"the boy who set the portable on fire".  That incident had something to do with
a big bot-bellied coal furnace in the corner of my first-grade classroom that
the janitor had to stoke occasionally with a bucket of coal.   It was then that
I discovered that where there is smoke, there is not always fire, but there will
soon be firemen.

 Oh yes; I failed first grade.  Not a great start huh?

Vaughn