Firefighters had to free a 15-year-old schoolboy whose hand became superglued to the loo handle.
Crews had to dismantle the toilet at the Thomas Bennett Community College in Crawley, West Sussex, to get the boy out of the cubicle on Thursday morning.
He was handed over to the school nurse with the flush handle still attached.
In a similar incident, a 13-year-old girl from Littlehampton, suffered skin damage after being glued to a toilet seat at Angmering School on 4 November.
Deputy head teacher of the Angmering School David Brixey said the matter was being taken "very seriously".
He added that nail extension glue was probably used in the incident and that students had been warned about the dangers of such pranks.