The married woman, identified only as Yokasta M, is accused of sending raunchy images of herself, some where she barely covers her breasts, to the youngsters.
The images and a three-minute YouTube video were circulated on social media, after a student posted them with the comment: “This is the teacher Yokasta, who tells us that she [suspend] us if we do not have relations with her .”
The images were eventually seen on a mobile phone of one of the threatened students by his father.
The parent reported the teacher, who works in a Colombian secondary school, to the authorities and she has since been arrested.
Local Le Mehor Television ran a story with the pictures, said to have been posted online by some of the students.
The television station is alleging the teacher from Colombia’s second largest city Medellin started exchanging the snaps with the teenagers using web apps.
But that then turned into demands for sexual favours in exchange for good grades, it is claimed.
Now the teacher faces a trial for extortion and sexual abuse of minors.
Her husband has asked for a divorce, according to ElNueve.com.