How does laser cooling work?

My 8th-grade science project was to mimic a laser.  We did it about 7 years after the ruby laser was invented ( May 16, 1960, by Ted Maiman at Hughes Research Labs).   
     Anyway,  our project was extremely advanced.   We took a magnifying glass and put a bright light behind it and put a match in front of the lens.   The match actually ignited about a half hour later.  We made the front page of our local newspaper because nobody had ever heard of a laser before.