It really just depends on your time management. A lot of the students who are extremely stressed out are the ones that have children, jobs, etc. Not to mention, a lot of them that don't have extra responsibilities tend to leave things until the last minute (or so it seems). My weekly routine is this:
Monday: prepare for clinical worksheets/concept maps DURING class.* I'll either finish them bout in 2-3 hours that I'm there, or I will finish up the last of it at home.
Tues: Clinical site. Come home. Study for 3-4 hrs. Take a break. Get back at it until I personally feel confident about the material.
Thurs-Sun: Because I have my own schedule of things, more than likely I'm studying something behind or ahead of the school's schedule. As long as I follow my set schedule, I am almost always "ahead" of the game and prepared for my exams. I pretty much will break down each lecture into halves or thirds depending on how much info is on the lecture powerpoint. So if I split it into thirds, that's three days that I spend studying the material to make sure I fully understand it. Again, this is all dependent on how long it takes you to study. Each individual is different as you may know. It may take you a day to understand Maternal information where as myself, it took 4 days.
*During lecture, instructors are mainly reading off the slides (which you can do at home). Rarely do they ever say "you don't need to know this" and even if they do, you can follow along to the recordings that many of your fellow students will have.
Some instructors do in fact have more expectations from others but you can either look at that negatively or you can look at that as a positive. Entirely up to you. Where some might be able to slack off, others may just end up being overly prepared (which isn't a bad thing).
Wish you the best of luck and just remember, no matter where you go... you will be a great nurse so long as you put your maximum effort in!