Hannah, as we know, stresses out a lot. She tries to study hard, but it's not very effective since she just ends up panicking. Poor girl. ):
Cho is that sort of annoying intelligent person who hardly studies at all but still performs wonderfully. She does make a point of reviewing concepts from earlier in the year, but she doesn't really go in depth with her revision.
Alicia doesn't really worry about exams (or much of anything). She tries to study a bit, but she usually ends up playing Exploding Snap or painting her nails or something instead.