1) Do I HAVE to take physics in high school?
Take a look at the admissions website, and more particularly, the recommended courses for students:
http://apply.jhu.edu/apply/apply.html It does not specify which science courses, but if you are hoping to become a physician, you'll have to take two semesters of physics in college, and it might help you out to take some in high school. It doesn't have to be AP or anything, but getting that background will definitely help you once you get here. (Just my personal opinion)
2) What are the class sizes like in the typical "pre-med" science classes?
Many of the introductory-level science classes are large, up to around 250 students for the biggest ones (Organic Chemistry, for example), but they have one class each week that is called "section," in which you meet in a group of about 30 with a Teaching Assistant. This is a great way to get more personalized guidance with the material. The professors also have office hours, during which students can come by to ask any questions they may have. So, the class sizes are big (it's in a big lecture hall auditorium), but it's really not so bad at all.
3) What are the classes like? (ex. Do the teachers lecture all class, how are the labs, etc.)
They're all pretty different (physics, biology, chemistry, organic chemistry, biochemistry, cell biology...). In general, though, I think it'd be safe to say that in the big classes, the professors tend to lecture most of the time but are VERY open to being stopped for questions (many of them will periodically stop and ask if there are questions, but others just have students raise hands and ask questions as they come up). Some professors put up problems for students to solve using a little clicker thing that sends in the answer electronically (and thus serves as a small portion of the grade and a sort of way to take attendance--like you get half credit if your answer is wrong, just for trying and being there)
I've only taken Physics lab and Organic Chemistry lab here. They're vastly different from each other. The Physics labs are scheduled for three hours, once a week, and the Organic labs are scheduled for 5 hours, once a week. The labs don't always take that whole time, but they are scheduled that way just in case. They are challenging but it's not too difficult to do well. The labs are all very well planned and organized, though the students are all pretty independent in the procedure. If there's questions though, there's PLENTY of help, both in and out of the lab.
4) Since I have pretty good study habits now and a very good work ethic, will I be ok at this college? (I'm nervous it will be too difficult!)
To be perfectly honest, lot of freshmen go in to ANY COLLEGE and assume that their high school study habits will get them through college. This can work for some people, but this doesn't always cut it. I'm not saying this will happen to you, but it's just something to keep in mind. The best thing students can do is to be very aware of how they are studying and be open-minded to try new methods if their old habits just aren't working for them.
The thing with college is that you'll find you have a lot of free time. For example, on Wednesdays, I have a class that ends at 9:50, then I have another class at 11. It is REALLY easy to just let that hour slip on by, reading news and drinking coffee, but if it's a busy week, I could get a good chunk of reading done for a class. Time management is key, and as a second semester sophomore, I'm still battling that one.
You will be
absolutely fine wherever you end up, it's just a matter of being open to changing the way you approach your work if necessary. That's what makes it so difficult, in my opinion.