Monica Avila, 34,was formally charged Tuesday with four counts of menacing and one count of possession of a weapon on school grounds.
Authorities say Avila confronted several students in the parking lot of Lake Middle School last Thursday.
Police documents say during an argument with the juveniles Avila pulled out a semi-automatic handgun, while inside her car, and told the students, "Look what I have."
Police say she then parked her car across the street while the students alerted adults in the area and called police.
Avila was later arrested.
Avila remains in the Denver County Jail under a $50,000 bond. She is scheduled to appear in court Thursday.