I'm going into second year commerce, so my experience with her in 1E03 is still fresh in my mind, and to be honest with you, she wasn't that bad. I remember feeling the same way as you when I looked at ratemyprof before starting her class, but she wasn't nearly as bad as people made her seem. Her report IS ridiculously hard, but its a good way to learn about how to do university reports. And as long as you actually put in the work, you should be able to do fine (my group put in about 3-4 hours per week from the start, and we got a 73%. Not the best mark considering how much work we got in, but decent enough to prove that its possible to do well. While some people do get negative, those are typically the people who didn't even bother to start until a week before it was due).
I also want to point out that, at least for last year, the report was only worth 10% of your grade (and presenting it is worth another 5%, though that was marked much easier). The rest of your marks come from midterms and the exam, which were incredibly easy in my opinion. They were all multiple choice and she didn't ask any of the annoying "all/none of the above" questions that usually kill people on MC tests. The questions were really straight forward and came either directly from her lecture or the text. I got an 11 (or A) in the course because of the midterms and exam. My biggest advice to you would be to GO TO EVERY SINGLE CLASS. She will ask the class "practice test questions" from her lecture, and I'd recommend copying them down because many of them will actually appear on the tests. Also, going to class is important because she stresses certain things that the book might not, and those things will also be on the test.
In summary, read your textbook, go to class, and actually make an effort on the report (start early! not the week before its due) and you should have no problem getting a good mark. Cossa is intimidating, and doesn't have the warmest personality, but she's a great prof. I learned a lot from her and I know I'm not the only one who walked out of her class on the final day actually wishing that I would have her again next year. Anyways, study hard and good luck (not that you'll need it of course!
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