Turkey Swim: The Nuuanu YMCA sponsors 2K and 1K races 8:30 a.m. Saturday at Ala Moana Beach Park. Entry fee $18. Applications are in Raceplace Hawaii magazine. Or call 536-3556.
Fern Safari: Charles Lamoureux gives a slide presentation on ferns, then leads a hunt at Lyon Arboretum, 8:30 to 11:30 a.m. Saturday. Costs $9. Reserve at 988-7378.
Taro Patch Party: Hands-on learning about a plant important to Hawaiian culture, 9:30 to 11:30 a.m. Saturday, Hawaii Nature Center. Costs $7. Reserve at 955-0100.
Mt. Olympus hike: Grant Oka of the Hawaiian Trail & Mountain Club leads a climb from Waahila State Park to a summit in St. Louis Heights, 8 a.m. Sunday. Six miles. Costs $2. Call 674-1459.
Hawaii In-Line Skating Association: Workouts 5:30 p.m. weekdays at Kakaako Park. Call 988-5299.
Free hike to Diamond Head: Meet the Clean Air Team at the Honolulu Zoo entrance, 9 a.m. Saturdays. Three miles to the top. Call 948-3299.
Honolulu Community Drum Circle: Drummers, percussionists and dancers gather, 1 to 5 p.m. Saturdays, Keehi Lagoon Park. Call 377-DRUM (377-3786).
Hash House Harriers: Social runs with Aloha group 3 p.m. Saturdays; call 948-AHHH (948-2444). Or Honolulu group 5:30 p.m. Tuesdays; call 948-HASH (948-4274).
Honolulu Marathon Clinic: Free training runs with Jack Scaff and staff, 7:30 a.m. Sundays, Kapiolani Park Bandstand. Call Norm at 247-4957. No meetings on three-day weekends.
Sports Acrobatics Hawaii: Hawaii Highflyers Trampoline Club for adults and kids, 4 and 5 p.m. Mondays and Wednesdays, McCully Recreation Center. Call Karl Vorwerk at 949-3747.
Waikiki Acrobatic Troupe meets 4 p.m. Sundays at the beach across Kapiolani Park
Bandstand; free workout at UH Studio Four 8 p.m. Wednesdays. Call Don Heafner at 536-7205.
Ikebana classes: Lillian Koide teaches flower arrangement 9 a.m. to noon Wednesdays at the Japanese Cultural Center. Tuition $30 per month plus supplies. Call 537-5765, evenings.
Honolulu Zoo: Zoo opens at 8 a.m. on the first and third Wednesdays of the month. General admission $6; $2 with Yum Yum Tree senior card. First Wednesdays feature a botanical tour at 8:45 a.m. for $2 more. Third Wednesdays, tai chi practice begins 8 a.m. Call 971-7174.
Nature Conservancy hikes: Two guided hikes a month to Honouliuli Preserve, home to more than 45 rare native plants and animals. Donation. Call 537-4508.