** Kahua, Hawaiian falsetto, 11:30 a.m.-1:30 p.m., Atrium Center Court, Aloha Tower Marketplace; free. 566-2337.
** Cerritos High School Band, noon-1 p.m., Fountain Courtyard, Royal Hawaiian Shopping Center; free. 922-2299.
Drum Joy! 6:30-8:30 p.m., 1007 Waimanu St.; learn basic hand-drumming techniques in playing traditional and contemporary African rhythms and songs from Guinea, Mali and Senegal; $10; loaner drums available by advance request. Register: 377-3786.
** Kilinahe, Hawaiian trio with hula, 6:30-8:30 p.m., Royal Hawaiian Shopping Center, third floor; free. 922-2299.
** "Aloha Waikiki," an all-Hawaiian music and dance show with a "Waikiki Memories" theme, 7-7:30 p.m. daily, DFS Galleria, corner of Kalakaua and Royal Hawaiian avenues; free. 931-2655.
** Pleasant Hawaiian Hula Show, 10 a.m., Waikiki Shell; free. 527-5666.
** Country Line Dance Class, 6-8 p.m., Ward Warehouse amphitheater stage; presented by Parents Without Partners; free. 262-6442.
** Kuhio Beach Torch Lighting and Hula Show, featuring Hawaiian Paradise, 6:30-7:30 p.m., Kuhio Beach stage, near Duke Kahanamoku statue; free. 843-8002.
** "On the Go with H2O," for ages 6-8, 9:30-11:30 a.m., Hawai'i Nature Center; explore a stream and its inhabitants; $14*. Register: 955-0100.
** Aloha Boat Days festivities for arriving cruise ship, 7 a.m., Pier 10; free. 566-2337.
"X-treme Science! Exploring Oceans, Volcanoes & Outer Space," a hands-on exhibit, 9 a.m.-5 p.m., Bishop Museum; continues through May 28; museum admission: $14.95*. 847-3511.
** Keiki Storytime, 10:30 a.m., Borders Waikele; free. 676-6699.
** Keiki Tuesday, with games and activities for youngsters, 10:30 a.m.-noon, Pearlridge Center Uptown; free. 488-0981.
** Tour of Hawai'i Theatre, with a demonstration on the 1922 Robert Morton theatre organ, 11 a.m.; $5. Register: 528-0506 (791-1305 for groups of 20 or more).
Behind-the-Scenes Tour at Bishop Museum, for ages 12 and up, 1:30-2:30 p.m.; $15 (plus $14.95* general museum admission). Register: 847-8243.