Hockey Rules! by Irene Punt

Tom is the envy of his friends. His teenage babysitter, Jeff, is totally cool ― he even plays road hockey. But things take a turn for the worse when Jeff becomes a ref and doesn't play favourites at a Hawks' hockey game. Jeff the Ref gives penalties and calls off goals; he plays by the rules. Things get out of hand when Tom and his friends fight back with mean chants and accidentally send Jeff a nasty e-mail. Tom comes to realize that it is better to play by the rules ― at home and on the ice.
 
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