It is believed the girls used a Snapchat filter so their speech would play backwards then saved the video and uploaded it to Instagram.
Horrified classmates picked up on the video and shared it on Facebook and Twitter along with comments laying out their disgust.
School officials who are now looking into whether the girls should face discipline.
They in fact uttered "surgeon cuff" and watched in amusement as the technology transformed their words into offensive racial slurs. It explains the video's original caption "serggin cuff" but staff said there is still "no excuse" for the footage.
"The video was then possibly uploaded into an app that plays it backwards, producing an entirely different sounding phrase. In this case, a very derogatory, offense racial slur.
"Our IT department is working to confirm this," Lane Findlay, the district spokesman, said in statement on the Weber School District Facebook page said.
"We are shocked by the conduct of these students and the contents of the video.
"However the video was made, it is completely inappropriate.
"We are trying to determine when the video was made, where it was filmed, why the students would engage in such conduct, and how the clip ended up on social media.
"School officials are in the process of making contact with the students involved and their families.
'Those contacted have already expressed regret and are extremely apologetic for what has happened,' he continued, adding that he hoped it would serve as a 'learning experience' for the girls.
"Racism, whether intentional or not, has no place in our schools or society.
"Certainly, there are no excuses for this type of behavior, but they are still children in a sense and hopefully this will be a learning experience for them and others," he added.
Critics feared the group were being let off lightly and that staff were making an excuse for their actions.
They called for the school to make an example out of the girls.
"Making excuses for this behavior allows these girls and others to believe that Weber School District is okay with the conduct and that you will continue to allow it. At some point, there has to be an example set.
"If not by cheerleaders that represent the school, than by the district who runs it," one said.
Others slammed them as "disgusting" and said "they knew what they were doing".
"They were fully aware of what they did and posted it because they thought it was funny," one person said.
"I'm sure they thought they were being cute and funny.... Until it was on social media," another said.
None have been suspended or expelled yet and school staff have not indicated how or if they plan to discipline the girls further.
