Learn to ski free in January. Ski areas and ski shops across the United States are sponsoring ``Let's Go Skiing, America'' month (Jan. 9-Feb. 8). The program kicks off with a free one-day learn-to-ski offer on Friday, Jan. 9, at participating ski areas, which includes a beginner group ski lesson, rental equipment, and access to beginners' lifts. A special coupon will also be available at nearly 1,000 ski shops nationwide, offering a package consisting of a lesson, rental equipment, and beginner's lift ticket for a maximum of $15 on weekdays or $25 on weekends. For names of participating ski shops in your area, call 800-238-2300. Trips for grandparents and grandchildren. Traveling together and sharing experiences is a good way to strengthen the link between generations. Grandtravel has developed several vacations for the individual family or groups, including a Dickens Christmas tour of London (Dec. 23-Jan. 2); President's weekend trip to Disney World (Feb. 13-16); Spring-break trip to the Southwest states to visit with and learn about American Indians (April 11-19); and summer vacation African safari (June 24-July 8 and July 22-Aug. 5). Other trips combine travel with such things as whale-watching, windjamming, gourmet cooking, arts, and visits to farms and festivals. Brochures are available from the Ticket Counter, 6900 Wisconsin Ave., Chevy Chase, MD 20815; or call (301) 986-0790.
Photo workshop in Papua, New Guinea. Adventurous camera buffs can experience the wonders of tribal New Guinea - while improving their photographic skills - on 16-day tour with Chris Rainier, a professional photo-lecturer. Trip members will be allowed to stand in a ``spirit house,'' watch a ``singsing,'' and visit a highland country so remote that first contact with white men wasn't made until the 1930s. Mr. Rainier's daily mini-seminars include photographing ethnic cultures, wildlife photography, flash photography, landscape photography, care of equipment, and other topics. The tour departs Feb. 1. Land cost is $3,790. For information, write Mountain Travel, 1398 Solano Ave., Albany, CA 94706. Call (415) 527-8100 in California, or toll-free 800-227-2384 outside California.
New Orleans Rail/Sail and Rail/ Motorcoach. Amtrak and the Bermuda Cruise Line are offering a rail/sail program through April 11. The program combines a round trip on Amtrak's Chicago-New Orleans train with a week's cruising aboard the liner Bermuda Star from New Orleans to Key West, Mexico's Yucat'an Peninsula, and Cozumel. Prices (per person, double occupancy) begin at $795. Another of Amtrak's tours, the Sunshine Express, leaves weekly from Feb. 6 to March 27, combining round-trip train travel from Chicago to Flagstaff, Ariz., with escorted motorcoach tours of the Grand Canyon, Las Vegas, Phoenix, and other Southwest attractions. Prices start at $705. For details, contact your travel agent.
Explore New Zealand by bike. Womantrek, an organization offering worldwide adventures for women, offers a combination bicyle and van tour of New Zealand, scheduled for Feb. 28-March 24. Average distance per day is 47 miles. A support vehicle carries luggage and spare parts and can give a lift to tired cyclists. Womantrek's participants have ranged in age from 21 to 68 years old. Women of average fitness are accepted with some bike conditioning done in advance. Cost is $1,645 plus air fare. It is recommended that you bring your own bike. For more information contact Womantrek, 1411 E. Olive Way, PO Box 20643 PR, Seattle, WA 98102; or call (206) 325-4772.
Mystery in Hong Kong and Singapore. There's more to investigate in the Far East than Chinese junks and rickshaws. Travelers on a ``Rendezvous with Murder'' tour must also discover ``whodunit.'' Among the supposed tour participants, hotel staff, tour arrangers, and neighborhood shopkeepers are professional actors and actresses who ``plot'' throughout the trip. They'll stage a complete, classic murder mystery, and it's up to the travelers to solve the puzzle. For more information, contact ICTS/ InterContinental Travel Systems, 4133 Taylor St., San Diego, CA 92110. Phone 800-428-7462 or 800-457-9515 in California, (619) 299-4217 in San Diego.
`Visit Thailand' year. The fact that King Bhumibol Aduladej celebrates his 60th birthday next year has not been lost on the country's tourism office as it proclaims 1987 as ``Visit Thailand'' year. The highlight of the year-long festivities will be the Royal Barge Procession on Oct. 16 - last seen during the Bangkok Bicentennial celebration in 1982. Other events include the Pattaya Grand Prix, the Siam Jewelry Fair, a floral float contest in northern Chiang Mai, a parade of brass bands from all parts of the country, the Songkran and Loy Krathong festivals, and the Elephant Show in northeastern Surin.
Big Apple's winter theater bargains. Every Monday at 8 p.m. the Actors' Playhouse at Sheridan Square in Greenwich Village presents a free program of one-act plays or scenes from plays (212) 741-1215. On most Monday evenings, free readings are held at the Actors Outlet, 120 West 28th Street, (212) 807-1590. Check Lincoln Center's Bruno Walter Auditorium and Juilliard Theater for free concerts, recitals, drama readings, dance, and theater programs. For half-priced day-of-performance tickets to Broadway and Off Broadway shows, visit the TKTS booths at Broadway and 47th Street (noon sale for matinees; 3 p.m. for evening shows) and 2 World Trade Center (sales begin at 11 a.m.). The Broadway booth also sells matinee-only tickets a day in advance. For a complete list of theater and other winter bargains in New York, look for free calendar of events at the NYC Tourist Bureau centers at 2 Columbus Circle - (212) 397-8200 - and Times Square.