10 days in Orlando and 4 in New York, family of 4, kids 18 and 11, what are the MUST sees and do's?

10 days in Orlando and 4 in New York, family of 4, kids 18 and 11, what are the MUST sees and do's?

I have bought New York passes for us all, plus Disney for 3 days in Orlando

Statue of Liberty, Ellis Island, river cruise around Manhattan Island, and then a selection of great museums to suit your tastes.

You will enjoy it..

What time of year? If it's soon (ie warm weather), hire some bikes in NYC and take a ride across the Brooklyn Bridge

As an 18yr old who went to Orlando  + NYC with a friend in February we both agreed that we  cannot emphasise the need to go to Universal Studios enough. I know this seems like pretty obvious advice, however Harry Potter World is both much better than I expected and took a lot more time than I expected -- some of the lines were incredibly long, even fastracking rides and going in single rider lines etc (definitly look into this at Dinsey World as well) and this was during the off season. We tried to do it in one day which wasnt enough, especially considering you want to go to both of the parks at Universal to take in both Diagon Ally and Hogsmead. Our strategy at disney world was to go to one of the smaller parks during the day (such as animal kingdom or epcot) and to then go to the magic kingdom during the evening, as by this is the most popular park, especially amoung younger children and we found they would largely head back to the hotel earlier thus reducing queue time for rides. 

With NYC I would recomend going to the top of the rock (at the rockerfeller centre) over the empire state building (mostly because you can then look at the empire state building), however I believe both are covered by the New York City Pass and in that case id recomend trying to get to the rockerfeller centre at sunset/ nightime (despite it being about -20 celcius I couldnt be drawn away the view was that spectacular). In regards to galleries/ museums I'd go to the MOMA above the rest, due to Stary Night, Les Demoiselles dÁvignon, the persistence of memory and the warhols etc. which I found more recognisable and quick frankly amazing to see all these really famous paintings all in one building. 

Cape Canaveral is less than an hour from Orlando.  Check the launch schedule, with 10 days you might be lucky.   There are also some places nearby you can do airboat tours of the wetlands and see aligators.

I always jump on the bus company web sites (contiki etc) or drive holiday web sites. This will give you a good idea.

if you are going to disneyland or universal studios, i can't stress enough to you to get the express passes for the rides at disneyland or universal, when i was there last there was a minimum hour wait per ride without them, or about 5 minutes with them, definitely worth the investment.

must see/do's in nyc include having lunch in central park, time square, having a nyc hot dog and pizza, as well as experiencing some of the cafe's in the upper east and west side.

also, if you are interested in going up the statue of liberty, i would recommend booking it now as its normally sold out many months in advance.

other must see/do's for florida, depending when you are there go to an nfl/nba game, florida has many teams in each sport, some good, some not good, so getting tickets should be relatively easy. go to miami beach and the florida keys, its a bit of a drive but well worth it.

In relation to Orlando, there's a whole advice industry devoted to making the most of your time at Walt Disney World - see for example The Unofficial Guide to Walt Disney World. Its also worth googling 'best time to visit Disney World 2015' even if you have dates booked, as this will lead you to info about how crowded different attractions will be at different times.

In NYC, further to tabs advice above about biking over the Brooklyn Bridge, riding bikes is also a good way to explore Central Park (lots of touts at the south-west corner), and there's a bike path along the Hudson River waterfront which leads to all sorts of interesting things. Try a diner or a deli for a different food experience. Ride the subway. Take a taxi. Check out Times Square. See some Broadway or off-Broadway shows. MOMA definitely, Museum of Natural History if you have time. Browse the guidebooks in the travel section at your best bookshop and buy a couple of different ones that most appeal to you. Get the family to look at them and start figuring out what you'd like to do.

My best advice is, having done some planning, go with the flow and respond to the family mood, weather and opportunities. Don't try to do everything on a long must-do list. Be prepared to split up and go in different directions to suit 18 and 11yo interests. Hope you have fun!