Kindergarten Cop

Kindergarten Cop is a 1990 American comedy film directed by Ivan Reitman and starring Arnold Schwarzenegger as John Kimble, a tough police detective, who must go undercover and pose as a kindergarten teacher to catch drug dealer Cullen Crisp Richard Tyson, before he can get to his former wife and son.

After years of pursuing drug lord Cullen Crisp Richard Tyson, Los Angeles Police detective John Kimble Schwarzenegger has him on a murder charge after Crisp shot and killed an informant Tom Kurlander who has given him information regarding the whereabouts of his former wife, Rachel Myatt Crisp, and his son Cullen, Jr. However, the informants girlfriend Alix Koromzay is unwilling to testify in court.Kimble, accompanied by detective and former teacher Phoebe OHara Pamela Reed, go undercover in Astoria, Oregon, to find Crisps exwife. It is believed that Rachel stole millions of dollars from Crisp before fleeing. The detectives are going to offer her a deal to testify against Cullen in exchange for immunity. OHara is to act as the substitute teacher in the sons kindergarten class at Astoria Elementary School. Kimble will discover the identity of the mother. ........

Source: Wikipedia