not a teacher
Putting aside the stronger terms of abuse that such behaviour would commonly attract (and yes, it happens all over the world), there would be a lot of regional differences for this situation.
If the kids are just doing it for a bit of fun, although it is very annoying, they might just be called "cheeky" or a "nuisance", possibly "rascals" or "scallywags", which are a little old fashioned but I still hear them. In Australia they might be called "larrikins" or "ratbags", but more likely "little b*ggers/b*stards".
If it's part of a persistent pattern of much worse behaviour they might be called "hooligans", "hoons" or "deliquents".
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