A female teacher at an all-boys school allegedly had sex with two of her students -- on the same day.

Cops say much-married June Kendall -- a teacher at Chicago’s Urban Prep Academy -- now faces charges of criminal sexual assault.

The 29-year-old woman allegedly had sex with one of her 17-year-old students early in the day then followed it up with a raunchy recess later in the afternoon with another boy, the Chicago Tribune reports.

Kendall's alleged liaisons with the two boys began over Snapchat, which got increasingly sexually charged. The teacher allegedly sent these students photos of herself in various stages of undress.

"Over time, (the Snapchat) messages became sexual in nature, and (Kendall) indicated to (one of the boys) that she wanted to have sex with him," according to a court document.

But someone saw the raunchy missives and reported Kendall and she was arrested.

Kendall’s husband is reportedly standing behind her.