Hall Monitor (1999)

High school incidents have dropped fifty percent since installing a hall monitor.  That's because Dan is essentially Dirty Harry.  He's got the voice, suit, sunglasses, hair, sideburns and gun.

A voch-tech kid decides to infiltrate the regular class area of the school as he is unaware of the new enforcement.  Consequently after being caught without a pass, the kid is shot in the leg while trying to escape.

This starts a feud between the voch-tech kids and Dan. The popular girl in school tries to date Dan and high school news reporters pop up once in awhile in search of s story.

Then someone starts killing the football players and a political struggle in the administration relieves the hall monitor of his gun.  At this point everything goes to hell in the school.

The description of a gun toting hall monitor sounds pretty good, but it's not used effectively for comedic purposes or for violence.  Ultimately it's a good idea which is never realized.