Imho every public education sucks but we don't have serious alternative. About cities, you can go anywhere. Main directions: Gdańsk, Kraków, Poznań, Wrocław and Warszawa. Other: every city with university or politechnika (it's something like university but more focused on technical studies: IT, mining, biotechnology, automatics, mechanics etc.). Also we've got medical academies and some private universities, but they need to follow the government plan for education so their level of education is low (everyone with money can finish private, paid studies).
As far I know in US you don't have final exams after every semester, on my University of Gdańsk (Faculty of Economics) we've got final exams for every subject (and 1/2 tests during the semester). E.g. my lectures are not obligatory but my friends from Neofilology needs to be on every lecture. Exercises are obligatory for everyone, on Politechnika they've got labs.
Cities with the highest amount of foreigners are Kraków and Warszawa. You can check amount of students from other countries here:
http://www.studyinpoland.pl/konsorc...iczby-studentow-ze-wszystkich-krajow-2016.pdf
(Ukraine, Belarus, Norway, Spain, Sweden, Turkey, Czech Rep., Russia, Germany, Lithuania, India, Saudi Arabia, China, Kazachstan, USA and yet more than 14o other countries).
About Poland in general I can link you this article:
Poland - Wikitravel It's good enough to get the basics. If you have more questions about Poland or Gdansk, just ask me.