First year 2-3 days/wk
Second year 2 days/wk
Third year 5 days/wk
These are just averages though, some weeks more, some less. During your 3rd year you won't have many lectures but many live classes. Also some classes require supplementary live classes. You won't have a lab until 3rd year. If you're involved in organizations you might be there more. I did drive to school a couple of extra days each semester for organization meetings.
ETA: this is how it was in Orlando, other campuses may be a little different, it depends on the facilitators.