Is it like being back in high school listening to lectures all day?
I thought of it more like uni tutorials. You won't be just sitting there listening to an instructor rambling on. There are three two-hour classes per day, but you'll also have the occasional field trip.
Do you get homework or assignments?
No homework or assignments, but you will need to study.
What style of tests are there?
They're a mix of multiple choice and written. The pass mark is 70%, although I seem to remember a couple of them might have required 80% There's at least one, quite often two, exams per week once you get past induction.
Is it permissible to take notes on iPad etc during class?
It was when I was there a year ago.
Realistically, how many hours should I expect to spend studying each night?
I was averaging about 2 to 3 hours per night, especially before an exam, and also studying on weekends. My average mark throughout the theory component was about 90%
I left the academy almost a year ago, so some things may have changed since then. I'm one of the old farts that didn't make it through the sim part of the course.