Reading this semester's essays, I note several common features that I haven't seen like this in past years:

- very few typos and grammatical oddities (which are otherwise common in first year students)
- very repetitive

I think I'm seeing Chat-GPT at work...

I just asked Chat-GPT to write an essay for the question I asked the students to write about and it's definitely using the same patterns and expressions that I see all over the student essays. So I fear I have to conclude that something like 75% of submissions are Chat-GPT plagiarized.
@philippsteinkrueger just test for it. There is e.g. the GPT Detector on this website https://www.writefull.com/
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@robertvief Thanks, will try!
@philippsteinkrueger Unfortunately, the free version has some limitations (maximum of words per query and limit of queries per day), but still useful to test the supicious essays...
@robertvief I'm afraid I can't even try, as I neither have Word nor Overleaf...