Capital Challenge Walk MS registration Two-day 50-kilometer walk, Sept. 21-22, 7 a.m., to raise awareness about multiple sclerosis and raise money for fighting the disease. Visit the Web site for details. Geico Building, 5260 Western Ave., Chevy Chase. 202-296-5363, Option 2. To participate, walkers must collect at least $1,500 in donations (for MS research and services) before the event. In addition, there is a $55 registration fee.

Pre-diabetes information The second of two classes on how to try to prevent diabetes by counting carbohydrates, creating a food log and exercising. Thursday, 9:30 to 11:30 a.m. Washington Adventist Hospital, Suite 350, 7600 Carroll Ave., Takoma Park. 800-542-5096. Free, registration required.

Affordable Care Act information Learn about the federal Patient Protection and Affordable Care Act, health insurance coverage and potential financial assistance through Maryland Health Connection. Sponsored by the Bethesda-Chevy Chase Regional Services Center and the Montgomery County Department of Health and Human Services. Thursday, 7-8:30 p.m. Bethesda–Chevy Chase Regional Services Center, 4805 Edgemoor Lane, Bethesda. 240-777-6534.

Drop-in tai chi student-led session. Friday, 9:15 a.m. Friendship Heights Village Center, 4433 S. Park Ave., Chevy Chase. 301-656-2797. $3; registration required.

American Red Cross blood drive Call to schedule your donation. Sunday, 8 a.m.-1:30 p.m. Christ Congregational Church, 9525 Colesville Rd., Silver Spring. 800-RED-CROSS.

Run for Recovering Heroes 5K and 10K Sunday, 5K, 3:30 p.m.; 10K, 4:30 p.m. There will be no race day registration. To benefit Pattons Veterans Project. Carderock Pavilion, C&O Canal National Historical Park, Cabin John. $40. 202-617-5708 or

Adventist HealthCare Walking Club meets 8 a.m. Tuesdays in the food court. Westfield Montgomery Shopping Mall, 7101 Democracy Blvd., Bethesda. 301-315-3030. Free.

Seniors fitness class For age 55 and older; an instructor leads a 45-minute class focusing on strength, flexibility, balance and cardiovascular endurance. Tuesday, 9 a.m. MedStar Montgomery Medical Center, 18101 Prince Philip Dr., Olney. 301-774-8881. Free, registration required.

Memory screenings Social workers will provide memory screening and discuss support and community resources. Tuesday, 10 a.m. Holy Cross Hospital Senior Source, 8580 Second Ave., Silver Spring. 301-754-8800. Free.

“Do You Hear What I Hear” Staff members from the Metropolitan Washington Ear provide information on services for the blind, visually impaired and physically disabled who cannot effectively read print, see plays, watch TV or view museum exhibits. Wednesday, 10:30 a.m.-noon. Margaret Schweinhaut Senior Center, 1000 Forest Glen Rd., Silver Spring. 240-777-8086. Free.

Square dancing and lessons New dancers welcome; come in casual dress. Wednesday at 7 p.m. North Chevy Chase Christian Church, 8814 Kensington Pkwy., Chevy Chase. 301-587-5861. $6.

Lunch and discussion of adversity Norman E. Rosenthal, psychiatrist, discusses his book, “The Gift of Adversity: The Unexpected Benefits of Life’s Difficulties, Setbacks and Imperfections.” Sponsored by Live & Learn Bethesda. Next Thursday, 11:30 a.m.-1 p.m. Bethesda-Chevy Chase Regional Services Center, 4805 Edgemoor Lane, Bethesda. 301-740-6150. 240-777-8200. $18, includes lunch. Registration required.

— Compiled by Lisa M. Bolton

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