Thanks. Can you help me arranging these sites into Day 1, 2, 3 at the most convenient? Anything else you'd recommend to visit? How about places to eat? Thank you again!

National Museum of Natural History
National Museum of American History
You may find yourself spending more time at each of these than you think, especially given the crowds that can form.
Bureau of Engraving and Printing
Not worth the time and effort.
Georgetown, Old town Alexandria or Alexandria Waterfront (is it worth for a quick stop?)
Didn't you say you were staying in Alexandria? Are you not staying in Old Town? If you are, you may as well spend some time there. If not, reconsider, as getting around the rest of the city can be cumbersome without a car.
The Southwest Waterfront
Not worth it. (Do not confuse this with the Tidal Basin, which is nice.)
Kennedy Center
There are free shows.
library of congress (do i need to reserve?)
No. Just show up for the tour.
I stay 10 mins away from DCA airport. So is my itinerary good/doable? I dont wanna over-plan. Thanks a lot!

I stay 10 mins away from DCA airport.
That doesn't mean anything. "10 minutes away" encompasses a wide area in many directions.
So is my itinerary good/doable?
See the above comments on the "good" part.
For a reasonable itinerary:
Spend one day at your two museums, then do the monuments tour. You could probably fit the Post Office tower in between.
The next day, you can visit the Capitol, Supreme Court, Library of Congress, and Eastern Market.
On your third day, you can explore other places you may have missed, like Arlington Cemetery, Spy Museum, Newseum, National Gallery, Air & Space Museum, Hirshhorn, American Indian, etc. (You won't get to all, so choose a couple and go.)

Hi,
I cannot help you with DC but perhaps I can with NYC as I was there just under 12 months ago.
Although I was not a rigorous person ( I was there mainly for business and not pleasure...:)) I can let you know of a really good restaurant in Brooklyn. It 's not outside dining but it's good food and quite inexpensive.
The Restaurant is called 'The Wicked Monk".
Here too is a link to good food places specifically in the Prospect Park area that may help you.
https://www.theinfatuation.com/new-york/guides/best-prospect-park-restaurants
As to gettting to the airport for your 7.30am flight, I would suggest booking a limo service. I was able to get one 24/7 when I was there and the commute ( no matter how many people or luggage) was all inclusive, $50. When taking into account bridge tolls and such, it's a cheap ride out to JKF. I will look though my email to see who I went through specifically to get that rate if you like. :)
Don't know if that helps you at all.
PS. I am wondering why you're not taking Coney Island in during your time there. As you're travelling with a teen, it could be a fun night out for you both. :) I had fun when I was there and I didn't even go on any of the rides! lol
Hi,
I cannot help you with DC but perhaps I can with NYC as I was there just under 12 months ago.
Although I was not a rigorous person ( I was there mainly for business and not pleasure...:)) I can let you know of a really good restaurant in Brooklyn. It 's not outside dining but it's good food and quite inexpensive.
The Restaurant is called 'The Wicked Monk".Here too is a link to good food places specifically in the Prospect Park area that may help you.
https://www.theinfatuation.com/new-york/guides/best-prospect-park-restaurants
As to gettting to the airport for your 7.30am flight, I would suggest booking a limo service. I was able to get one 24/7 when I was there and the commute ( no matter how many people or luggage) was all inclusive, $50. When taking into account bridge tolls and such, it's a cheap ride out to JKF. I will look though my email to see who I went through specifically to get that rate if you like. :)
Don't know if that helps you at all.
PS. I am wondering why you're not taking Coney Island in during your time there. As you're travelling with a teen, it could be a fun night out for you both. :) I had fun when I was there and I didn't even go on any of the rides! lol
Thank you! Any casual restaurants and seafood places you'd recommend in Manhattan? And may I get the info to book the limousine? I've never been in one and $50 sounds good!
How many days did you spend in NY? And can you share your itinerary?

Hi,
I cannot help you with DC but perhaps I can with NYC as I was there just under 12 months ago.
Although I was not a rigorous person ( I was there mainly for business and not pleasure...:)) I can let you know of a really good restaurant in Brooklyn. It 's not outside dining but it's good food and quite inexpensive.
The Restaurant is called 'The Wicked Monk".Here too is a link to good food places specifically in the Prospect Park area that may help you.
https://www.theinfatuation.com/new-york/guides/best-prospect-park-restaurants
As to gettting to the airport for your 7.30am flight, I would suggest booking a limo service. I was able to get one 24/7 when I was there and the commute ( no matter how many people or luggage) was all inclusive, $50. When taking into account bridge tolls and such, it's a cheap ride out to JKF. I will look though my email to see who I went through specifically to get that rate if you like. :)
Don't know if that helps you at all.
PS. I am wondering why you're not taking Coney Island in during your time there. As you're travelling with a teen, it could be a fun night out for you both. :) I had fun when I was there and I didn't even go on any of the rides! lol
Thank you! Any casual restaurants and seafood places you'd recommend in Manhattan? And may I get the info to book the limousine? I've never been in one and $50 sounds good!
How many days did you spend in NY? And can you share your itinerary?
Hi Sunset06,
I have to be honest with you. I personally did not like Manhattan. That may have had a lot to do with the timing of my flight in ( I travelled from Australia-LAX-JKF, consecutive flights back to back :/) so my time there for "pleasure" was fleeting. I stayed the first night at Hilton Homewood Suites Midtown Manhattan. ( I would not recommend it to anyone to be frank...nice room but NIL customer service) but the limo from the Airport right in to Manhattan, was all told $71.00 and during peak hour traffic. ( it's a longer ride than directly to Brooklyn and incurs more toll costs for the ride - BTW that also included to the tip as well). That was with: http://www.lincolnlimousine.com/ They actually trekked me from Manhattan to Brooklyn for $50 and then on my trip back to JFK FROM Brooklyn, $50. as well when I needed it. Cool thing is, they accept CC bookings online and do not charge you, if you choose to pay the driver direct but your booking is secure no matter which way you want to pay. :)
The rest of the time I was staying with a friend ( and business associate) in Brooklyn ( close to Manhattan Beach, Brooklyn) and I was fortunate enough to have her car to use when I needed it. As such, she and I ate at local digs close to her place and the food was great no matter where we went.
I was there from August 8th until August 20th, 2016 ( yes...the HEATWAVE). Any down time I had, we went up to Long Island...Greenport. SO pretty and quaint. I took in some winery trips and such. ( again, not suitable with a teen in tow). Like I said, most of my time was for business that trip. Next time I may go sight seeing and I can't recommend any restaurants in Manhattan. I went to a Pub very close to the hotel I stayed when in Manhattan and the food looked good, but I didn't eat anything as I just wanted to have a drink and go to bed pretty much after my flights. :/
I am sorry I cannot help you personally any more in that regard but I also have other friends who are locals IN Manhattan and I can put my feelers out for them to suggest places that perhaps "only the locals know" ;)