How are third year and fourth year courses different in terms of workload, difficulty, expectations etc? Is there a big jump from second year? I am planning on taking a fourth year nursing course in third year and would appreciate any insights. Thanks so much!

It really depends on the course that you're taking. Fourth year courses are just like any other courses, so there are bound to be some that are workload heavy vs. those that are light workload. You should maybe look for reviews of the course you want to take to see what it's like. Personally I've found that a lot of the fourth year courses I've taken in my own department tend to be more flexible (in that they don't have midterms or exams) because fourth year courses tend to be smaller, critical thinking or inquiry based so the work is more hands-on rather than textbook based. That being said, because you're in fourth year, the professors usually expect you to have a grounded knowledge from past years.