The discos, Toroko on Policarpo Toro and PiRiTi on Ave. Hotu Matu'a, crank up on Friday and Saturday nights. During the peak summer season (December to February), they may operate other nights as well. The doors open around 2230, but nothing much happens before midnight, then the action continues until dawn.
The Kari Kari Ballet Cultural performs at different venues a couple of nights a week (the days vary according to flight schedules). This skillful traditional troupe formed in 1996 is well worth seeing. Also ask about cultural shows by the Matatoa dance troupe which performs at different restaurants around Hanga Roa.
Sunday at 0900 there's singing in Rapanui in the Catholic church. April-October you can watch the local soccer teams compete in the field opposite Caleta Hanga Roa. Matches start at 2000 on Tuesday and Thursday, at 1400 on Sunday. Expect everything except church to start late.