Everything we know about American high schools we've learnt movies and TV, so from what we can see in Jarayray Seashelle's YouTube clip, their school is 1. Real fancy and 2. Reaaaally lax on noise and rowdiness. So when they start doing their own mini Glee scene, instead of getting told to shut the eff up, this happens. We don't know who 'Mr."Thirst Gawd" Fanning' is but with a surname like Fanning and moves like that, we're assuming he's got some Irish in him. And as we all know, in any situation with a foreign people, when in doubt, Riverdance.
(If you're wearing earphones, you'd want to do yourself a favour and turn the sound down before you hit play)