Voir Primeval, Season 4 - Episode 4

Saturday detention is chaos when a deadly Therocephalian attacks a teacher, allowing the kids to run riot.  The team are faced with not only tracking down the creatures, but fighting against the antics of a group of terrified students.  Finding a Therocephalian nest in the school, Connor enlists the help of the kids to help defeat the creatures before returning them through the anomaly.