Spooky School (2000)

Jung Yoo-mi and her students come to Yoo-gok Elementary School in a rural town as a part of an exchange program. They are spooked by a campus ghost story told by Kim Gye-dong, a teacher at the school. But the students' curiosities get the better of them and they decide to search every nook and cranny for the ghost. Unfortunately, it is Yoo-mi who runs into the ghost when she goes to the bathroom at midnight. The campus ghost story now becomes real to everyone at the school. The fearless threesome, Tae-suk, Chul-soo and Hoon, decide to go to the annex building where the ghost is believed to reside in. But Man-duk warns them vehemently against going there. When Tae-suk receives a message that the school is cursed, he and his friends sneak into the annex building to uncover the mystery once and for all. His friends are chased by the ghosts and now Tae-suk must find his missing friends.