I think at leadt three days if you are not able to get tickeys for early in the day each day. There are 8 floors and a lot to see. Be prepaired, it is a lot of walking and wheel chairs (if neede) are first come first serve.
Definitely two days. If you are a VET, it's free for you, wife and two kids.
Yes, early as in months in advance. However, same day tickets are available.online at 6:30 am. Walk up tickets are available at 1 pm weekdays.
I used the same day pass. Just go to the museum website and register, the slot open 6.30 am daily. You will see other option to register on the website.
Plan on 2 days. Get your tickets early online. They sell out quickly. Definitely eat at the museum cafeteria.
Thanks! Your answer is awaiting moderation.