Off-Peak Season (September-February) Walk-Up Weekday entry begins at 10 am Monday through Friday. You can also try day pass by going to this https://www.etix.com/ticket/v/11570/national-museum-of-african-american-history-culture-same-day?displayType=list
Same day passes for weekends can be booked online on the day at 6:30am and 9:30am. On weekdays it's a walk-up entry. For groups you have to book in advance.
Our school just had a field trip to the NMAAH on Sunday. We were required to have group tickets and had to go through security. Make sure you get yours online.
Call your state representative, tickets r required only on weekends.
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