Hello R,
Thanks for your question, I\’d be happy to help! As I mentioned I studied Mathematics at the faculty of science and engineering. I will assume that your son is looking at a program from the same faculty. Regarding the level of English of teachers I do not necessarily agree with the negative opinions you saw. Certainly, there are a few teachers that may be slightly less fluent in the English language than others. Nonetheless, the switch from Dutch to English has been made (in my best guess) at least a decade ago. That means that all the staff (both teaching and any other related staff) speaks English to a perfectly acceptable level. In addition to that, a lot of the teachers are actually not Dutch, and I feel like this contributes to an international environment.
Regarding the focus on memorizing I again can only comment on my own field of studies. Especially in bigger courses I can see why one would feel like the focus is on memorizing, but this has more to do with organizational aspects. To create an exam for let\’s say 150+ students, it has to be easy to grade and treating all the topics of the course. This leads to that exams can be quite similar over the years. However, I have this experience only with few of the particularly large first year courses, and I can also see why this is done, since they teach essentials that simply every student needs to have. Once you progress to second and third year courses, you will get more into creating a deep understanding of the topics relevant to your field.
I do not want to give you a smoke and mirrors image of the RUG. However, comparing the RUG to the University of Leiden, where I am now doing my master, the RUG (and Groningen in general) is further internationalized than Leiden and the UL.
To summarize: I feel like the overall English level is highly developed and that all communication, whether it is in class or through the communication channels, is done in English at a more than sufficient level. The academical focus (in the Bachelor) is in my opinion highly focused on laying the foundations for pursuing higher mathematics (or any other field you like). Sure, for some courses one might get away with memorizing previous tests and applying those at the exam, though at some point this will not be possible anymore and your son will be forced to understand the material 😉
Let me add as a last note that I want to highly recommend the RUG to your son. I find that everybody, both in the University and in the city, speaks good English and that there are a lot of facilities for students (sports, music etc.). In addition to that, there is a lot of room to tailor your program (possibly study a semester abroad) to your needs. I hope I have helped you enough and feel free to ask another question if you want.
Kind regards,
Jelmer