If you’re in a French high school, then your choice is different:
Do you want to remain in the same style of teaching and general academic environment as before? If you live in France, do you want to stay in what’s most familiar to you?
then ==> Bachelor Polytechnique
Do you want to live in a different country and experience a new culture?
then ==> McGill or Cooper Union
McGill v.Cooper Union
McGill is well-recognized in Europe and in North America (it’s often jokingly refered to as “Canadian Harvard”, although it’s not quite true, first of all because it’s a large public university). It’s not that selective for Canadian applicants, more so for internationals, but the classes are tough and require a lot of work - many have to drop out or take longer to graduate (think of the EPFL model).
There are about 40,000 students, classes are huge (in the hundreds) and lecture-based for the most part. During your first year, it’s likely few professors will know your name. You’ll have TA’s (PHD students who teach labs or discussion sections) and most contacts will be with them. If you make an effort you may get to know professors through office hours and get a chance at working in a lab.
You’ll be challenged not just academically but in many other ways since you’ll be surrounded by the best and brightest from many countries, all with different experiences (both personal and academic). There’ll be many social opportunities.
You need to be autonomous, not hesitate to ask questions during office hours (and of course, actually go to office hours), use the tutoring services, etc. You’re in the middle of a bilingual, cosmopolitan city that’s one of the best in the world for college students.
The drinking age is 18, meaning you can go to clubs or socialize in bars.
After your first year, you need to find your own housing with classmates and deal with grocery shopping, paying utilities, etc, on top of doing well in your classes, using career services, and enjoying your time. You’ll likely congregate with classmates in the neighborhood near McGill.
Cooper Union is a specialized university. It’s tiny, closer in size to a French “grande école”: about 900 students, including about 500 in Engineering. The school is highly selective and most students come from NYC (however it’s a very diverse school, because NYC is diverse).
As a result, education there is more personalized than at McGill: 3/4 classes will have fewer than 20 students and almost all fewer than 40. You’ll have a personal adviser who knows you. Lots of learning is project-based and/or experiential, with maker spaces and labs linking STEM and industry. The “invention factory” summer program is fairly representative of their philosophy: you and your team design a product and go from idea to conception to production to testing to patent in 6 weeks. Obviously, the career center will help you find (paid) summer internships and graduating from a US college with a STEM degree will qualify you for 27 months OPT (job) minus the time spent on CPT (internship).
It’s a very urban university: there’s no campus per se and most students come from NYC so they commute. Students use the city for their entertainment (no bars nor clubs till you’re 21 though, so you’ll depend on fellow students for parties). Most non commuters live in the 1st year dorm. After that, they have to find apartments to rent in NYC, which is very difficult&expensive, and requires you to look with friends as early as October for the next Fall, perhaps from current seniors who’ll recommend you to their landlord. Students live all over the city and the commute can easily be 1hour long. However, that city is NYC, so there are tons of things to do and see at any time of the day or night. Socially, though, it’s more isolating than McGill.
As a result, transferring into these colleges is is almost impossible.