A Chicago High School has banned students from sexually explicit dancing, known as 'grinding', ahead of a school event.

Administrators at Mundelein High School in Illinois have written to parents ahead of the upcoming 'Turnabout Dance' on February 11, warning students that 'back to front' or 'any other sexually explicit dancing' will not be allowed.

The ban comes after students and staff at Central High School in Colorado created a controversial video that showed pupils grinding and 'freaking' in a bid to show the rest of the school what was appropriate for upcoming school dances.

In a letter addressed to Mundelein parents, Principal Lauren Fagel said that freaking or grinding on the dance floor was becoming an increasing problem.

She wrote: Please excuse the graphic description that follows.

'Grinding', a sexually explicit, back-to-front style of dancing has become increasingly popular at our recent dances.

In most cases a student stands directly behind the partner. At the same time, he/she presses their pelvic region against their partner's backside. As the music plays, the students then thrust or 'grind' to the beat of the music.

Sometimes, the person in front will even bend over as they dance, placing their hands on their knees or the floor.

Fagel then goes on to say the practice is making other students and chaperone staff uncomfortable and that anyone caught grinding would face expulsion from the event and a possible future ban on other dances.

Last month students at Central High School in Colorado were shown a video during assembly to illustrate what was deemed inappropriate at school dances.

The video, which was created with the consent of staff, shows students dancing in a sexually suggestive manner before being told off by staff.

The 'anti-freaking' dance film caused outrage after it was leaked to parents.

School board officials were later forced to apologise adding that the video had been taken out of context.