Bitter-Sweet (1996)

Original title: Słodko gorzki

Mateusz, Igor, Marlon, and Paulina attend the same high school. After returning from Budapest, Mateusz learns that one of his classmates, a boy named Bąbel, has hanged himself on the school playground. Distraught by the tragedy of his friend, he decides to conduct his own investigation into his death. Igor, who found Bąbel's body, knows what happened but is afraid to speak up. The same is true of other students, and even teachers, who are mainly preoccupied with their own personal problems. He sees his last chance in a conversation with Paulina, who is in love with him, but the girl leaves him alone in his fight to find out the truth.