Uburger is very popular with BU students. Max Brenner is a fun experience for dessert…Of the historic sights my favorite was the Old North Church with the extra tour. Loved seeing the famous bells! Duck Tours fill quickly, and are the very best kind of kitsch. They include dumb jokes, an interesting take on hostory, and a beautiful ride on the Charles. Great way to rest your feet, too!
If you are looking at city schools, you have absolutely the right idea to check out the city. I was a student at BU and spent a lot of time walking around the city. It is not even that far to walk from BU to the Public Garden or even further, like the waterfront. I also took the T (or walked) Harvard Square. If you are looking at BU and want to see a student neighborhood, go to Allston, e.g. intersection of Commonwealth Avenue and Harvard St., maybe Coolidge Corner in Brookline too, though the latter is less student-y. For Northeastern, I am less familiar with the student places even though I went there much more recently for grad school. Check out Hemenway St. where there are a lot of student apartments to get a feel for the immediate neighborhood. Yes on Davis Square too, especially if Tufts is on the list. As for Lexington and Concord, well, I live out that way and it is interesting if you like history, getting outdoors and its a nice place to raise children, but we don’t have a lot of college students hanging out here!*
*except certain summer jobless loafers-at-home 
Ditto on Toscanini’s. Also, my kids love Redbones BBQ in Davis Square.
some assorted favorites for my kids this age and their friends: they love getting a cannoli at Maria’s Pastry in the North End, walking around Quincy Market, hanging out at the waterfront near the aquarium, Otto’s Pizza, Anna’s Taqueria, walking around any of the squares – Davis, Harvard, a stop at Sugar Heaven on Boylston and hanging out in Copley Square, Revere Beach (accessible via T), walking over the Mass Ave bridge, and, as old as they are, they still enjoy finding the Make Way for Ducklings statue.
There is a museum at MIT which might be worth checking out if that is along your route.
My daughter’s English teacher is from another area of the country and her family is visiting this summer. She asked the kids to write about any must-do’s while in Boston. My daughter said she recommended suggested visiting the Holocaust Memorial, particularly at night. If you aren’t familiar, it is adjacent to Faneuil Hall.
Also - if it suits your travel routes, try taking one of the MBTA water shuttles instead of a cab or train.
I have a lot of great suggestions here. Question about the best app or site where I can get the best T routing. The MBTA site suggests making all these connections/transfers where sometimes you are only on that train for 2 minutes. Just wondering if anyone knows of a site or app that realizes it makes sense to walk 6 minutes to connect to a better T route then taking 3 different T trains and adding 40 extra minutes to your trip.
Google maps does well on transit – both subways or buses.
re: MBTA be aware you will pay twice if you get out completely and go back in. There are two underground stations that have a tunnel connecting: Downtown Crossing (Red/Orange lines) and Park Street (Red/Green lines) are connected by a walking tunnel, so you can either ride or walk. I will usually walk between these. Is this the connection you are talking about? The T trains just come regularly. The commuter rail (Purple line) actually runs on a schedule. Send me a private message if you have a specific question. I am happy to answer.
Another thumbs up for Google Maps for transit use. It’ll give you several mass transit route options in time order. Even more useful, you can specify a specific time when you want to leave (adding on, say, 15 minutes as you’re preparing to pay the bill) and not feel you have to rush out to catch the train leaving in one minute.
I have to challenge the presumption that teenage boys have no interest in art museums. Both my sons enjoy them, and have made a point of visiting great museums on their own.
We are all packed and ready to catch our early morning flight. I made a list with many of the suggestions above. One more question, where exactly is “The North End” and “Back Bay”?
Welcome to Boston! You’ve probably figured out by now the Back Bay is the area west of the Public Garden with the grid pattern of streets with cross streets in alphabetical order. Commonwealth Avenue is the main residential street running down the middle and Newbury and Boylston running parallel are shopping streets. The closest T station to the North End is Haymarket, I think. Old North Church is a landmark.
I second Redbones in Somerville. If you want an upscale, but casual and cool restaurant try Island Creek Oyster Bar in Kenmore Square. It’s so great. Also, another good place for a lobster roll is the Barking Crab on the waterfront. Everyone loves Harvard Square. That would be my first place to take a young person to see the area.
Another vote for Island Creek!
My daughter works at Modern Pastry, across the street from Mike’s and a competitor. And of course, the best canoli in Boston. 
Hope you have a good trip. Weather will be better Wed.
We are back from our trip and we both had a great time. We were able to take the T or walk the entire time. I had my app for uber and Lyft but the T is set up so well and there was always a train when we arrived or within minutes. It really is the way to go in Boston. We had full tours at 3 schools and a full engineering presentation and tour at one of them. We also walked through a 4th school. Of the four, two are going on my son’s “apply to” list and one of them is high on the list. We also visited many of the areas listed above and had some great seafood. The weather was great for walking, about 80 degrees and only rained one day for about 10 minutes. Even though it was summer, many of the schools had summer sessions going on so the campuses were active. It really was a productive trip.
Glad it worked so well and the T treated you well also. It is a great city for school. I had much of grad school here and loved it. I did my undergrad not in a city and liked that better (I think) because it is easier to bond when there aren’t so many external activities. But, ShawD did undergrad and is doing grad school here very happily.
Not a fan of Redbones though I had a better meal for lunch than dinner - eaten their several times. There is no really good BBQ in Boston, which is why I recommend lobster rolls and ice cream - things that Bostonians understand. The best place is off I-90 on the way back to NYC. Forget the name, but it’s far better than anything in Boston.
Glad the OP ate well and had a good time and found colleges her kid likes.
Mathmom - have you tried Blue Ribbon BBQ?
We’ve eaten at the Arlington branch twice. Underwhelmed.