Jiggy McCue: Maggot Pie by Michael Lawrence
There is a tradition in Jiggy's hometown by which the night before a boy's first day at school his father takes him to the Piddle Pool near the old quarry. Boys pee in the pool for a lucky school life. But Jiggy's dad never took him...and now Jiggy wants to change his run of bad luck. One night, mid-piddle, something happens - and a genie rises out of the water. Will Jiggy's luck be reversed...or will it just get worse?!