Shalom from Israel!
AHIS100 has been messed about with in recent times, when i did it it was taught by a different lecturer and was called 'Oikos to Polis', so i can only comment on it as it was then.
Like most 100 lvl AHIS courses, it's a pretty general introductory unit that covers a lot of content from a wide time period. When i did it the unit covered the evolution of key concepts of Greek culture from the archaic to classical period.
I remember enjoying it immensely, however a lot of that may have had something to do with the lecturer at the time, who was fantastic. I'll keep my sentiments on the current lecturer out of the public sphere, but you can PM me if you're interested.
The assessment was fairly straight forward, 2x 1000 word tute papers, 1x 2-3000 word major essay, 1x final exam and tute participation. Mind, this was several years ago, it may have since changed. This unit also has a heavy reading component, but this is normal for most AHIS units.
Do keep in mind that while the first year units are content heavy, their main purpose is to teach you how to think and analyse critically, not necessarily to mash huge amount of info into your brain as in HSC history. You might almost be at an advantage in this respect, some school leavers have trouble adjusting to this new way of approaching history and tend to do poorly without realising why.