Dropping off old scarfs and mittens at a local charity will make the basement tidy. But volunteering a day of your time may be more inspiring.

The Therapeutic and Recreational Riding Center, a community service organization offering horseback riding therapy to physically and mentally handicapped children and adults, needs volunteers.

"We need people to lead a horse and help teach a handicapped person riding skills," said Sheryl Hackman, director of special events and volunteer coordinator at the riding center.

The purpose of the center is to provide an enjoyable activity that handicapped persons can perform while exercising their muscles.

"We offer a nonclinical, naturalistic environment for our riders and they really enjoy a bond with the animal," Hackman said.

After completing a therapy program, clients are mainstreamed into recreational riding programs also available at the center. The group rate for therapy sessions is $10 per hour. Recreational sessions are $12.50 per hour.

Volunteers must be at least 14 years old and willing to donate one to two hours (preferably daytime hours) per week. The center is located at 15920 Emory Lane, Rockville. Call: 924-2716.

If you find horses intimidating, there are countless other volunteer activities available. The Volunteer Clearinghouse, an informational and referral service for people seeking volunteer work, has a listing of more than 650 nonprofit agencies in need of someone's time.

"It is a good idea to get together with friends or family and volunteer your time," says Angelina Austin, assistant director of the Clearinghouse. "When people do things in groups during the holidays, it is more fun."

Ideas of possible activities range from throwing a party for senior citizens and foster children to working with the homeless or hosting a foreign visitor. To help people decide, the Clearinghouse provides a holiday "Community Wish List" of area agency needs.

The Clearinghouse places more than 1,500 people a year and urges people to consider volunteering at any time. "This time of year, everyone feels guilty," says Alice Franks, director of transitional volunteer programs at the Clearinghouse, "but people are hungry year round and there are all sorts of programs to get involved in."

For a copy of the wish book, call 638-2664 or 483-2702 during evenings and weekends.