Go to the website to request your tickets.
https://event.etix.com/ticket/e/1004039/timed-entry-pass-washington-national-museum-of-african-american-history-and-culture?
On-line on their website. You may also try your luck with walk-in.
Go to the website and click on time passes. You have to do it early in the morning. They will email the passes to you.
I visited the museum as a part of a conference administration, but I believe you can either book it online in advance, or get the daily tickets at the door.
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