Are you looking for a student's-eye view? (Although obviously you won't be a student)
We did about an hour of Greek each morning, Athenaze I books and homework set; then I think two lectures before lunch and two after, on a variety of topics. For Classics we didn't have to do a research-based lecture, although History, English etc. did; we just had a tutorial at the end of the week, in groups of three, on a passage we'd been given. (My group was on Catullus 62, in English, with some extra passages, such as a bit of Apollonius of Rhodes, also provided.) A few activities - visited an exhibition at the Ashmolean, as Classicists, but there were also general evening activities, including a barbeque, a bop, and smaller group activities like salsa. Then back to the college common room until sent to bed, usually for a game of Zip Zap Boing [such fantastic memories of that
]. Anything I've forgotten?
What else?
Think from a mentor's PoV, it involved going to some of the activities, foregoing alcohol for the week (my mentor was getting withdrawal symptoms by the time we left), giving advice (particularly on Personal Statements) and making sure you take people where they need to go and deal with any medical mishaps, etc.