Play hooky

 "There is no widely accepted explanation for the word 'hookey' or 'hooky.' An Americanism that arose in the late 19th century, when compulsory attendance laws became the rule in public schools, 'hooky' may be a compression of the older expression 'hook it,' 'to escape or make off,' formed by dropping the 't' in the phrase. Or it could be related to the old slang word 'hook,' meaning 'to steal,': kids stealing a day off from school. 'Hooky' has so often been associated with going fishing that it may even owe its life to 'getting off the hook' the way a fish can; anyway, school is often insufferable as a hook to schoolchildren and many kids squirming in their seats all day look like they are on a hook." From "Encyclopedia of Word and Phrase Origins" by Robert Hendrickson (Facts on File, New York, 1997).