My husband and I and our 2 teens (14 & 16) are planning a 5-7 day Washington DC trip in April 2023. We are at the beginning stages of planning! I'm trying to figure out what things to "group together" geographically each day, and also think about what museums/attractions need timed entry. I don't even know how to get these tickets yet! I would appreciate any input! Thank you

Pertains to the Smithsonian museums: https://www.si.edu/visit/hours

Timed entry required for:

• National Museum of African American History and Culture
• National Air and Space Museum in D.C.
• National Zoo
• Cooper Hewitt, Smithsonian Design Museum

Also, this is an overall good reference: https://washington.org/DC-faqs-for-v...equire-tickets

I don't think there is any one source because there are private museums and venues, Smithsonian places and then other govt-run museums and venues. So there isn't just one place that lists everything. You really should visit the website of the places you most want to go to be sure, and within a month or so before you want to go as things could change, of course.

Very few places actually require an advance timed entry ticket, some just recommend it. But the places that say they require it or are so busy you really should not count on a walk-up are:

Library of Congress
Archives
Capitol building
Phillips Collection (they say they require it but I could swear I've gotten in at the door on a weekday)
Spy Museum (you might get in there last minute)
Holocaust (you also might get in there as a walk-up, someone did last time I was there but April is super busy so get a ticket if you really want to go)
Zoo
African American History and Culture Museum (I've gotten last minute tickets fairly easily at times if I'm willing to go 2-3 pm, checking same da)
Air and Space Museum
Wash Monument
Pentagon
Mount Vernon

The last above link isn't bad but is rather out of date as the LOC has required timed tickets for maybe a couple years, I believe. Also the Supreme COurt has been closed to visitors for a couple years due to public violence and safety (and COVID I suppose). It just recently reopened again, in fact, but if you want to sit for oral arguments you check the calendar and then it is solely first come first served standing in lines outside.
The Capitol also just recently reopened. The Bureau of Engraving is closed to visitors.

YOu get tickets just by going to a particular venue's website. You should be able to find it by googling the name of the place