Walk the brooklyn bridge to DUMBO. You'll see signs to scenic area. Its a chilled place unlike some of manhatten and good for pictures. The carousel there is fun too even for adults. Get the boat back to manhatten. time out market there is good for lunch.
I enjoyed summit 1. Go early in the day for it to be quiet. Its an insta/tiktok teens dream, but do NOT wear a dress! Mirriored floors.
Empire state building is iconic to go up but you get better pictures from top of the rock. Depends if you want iconic or good pictures.
Wander a lot the high line is a nice wander. Look for markets. Have the teens tell you where they'd like to go too.
Do the statue of libery and ellis island. But book in front onine with the statue of liberty people. So many touts around there selling dodgy things.
Be cautious of street vendors who dont display prices. So many people have been conned by ice cream vans .
New yorkers are geberally lovely and helpful. But there's some dodgy people like any big city. So just be sensivke as you would in any big city. Times squares a bit manic.
I enjoyed the 9/11 museum. Its depressing but one of those places i think is important to visit. But with teens be cautious as to whether they're old enough to take ig. Its a tough visit.
Theres some great fb groups for nyc tourist tips. Join them. You'll get loads of ideas.
If you're coming from the UK check out the MPC app for quicker entry. Yellow cabs are fixed rate into the city. Also get esims if your phones are enabled for them. Cheaper than roaming charges and means you can use google maps to find your way around. You can get one ans the other tether off it as needed. I used airalo but there's others.
I love NYC i've been 5 times and would go again tomorrow if i could. Planning a trip for my 40th next year! Its a love/hate city. Oh and as others have said comfortable shoes for sure. Something with a good sole (sketchers etc) as you'll be doing a lot of pavement walking. Traffics insane so its quicker to walk.