I regret picking Music 2 How the hell can teachers fairly mark someone's playing on an instrument if they don't play it themselves? Also all this composition crap, a musicology essay that we have 20 minutes to write and friggin melodic dictation and sight singing that we (well at least my class) has never been taught how to do. Plus, the choices for the pieces you have to play are so restrictive. Add to that that the whole subject is pretty much an ATAR killer and you get the biggest regret of my HSC year
The markers don't need to know how to play the instrument. What they mark you is on how technical ability, stylistic understanding, your understanding of your role as a soloist or ensemble member, expression and if you or just play the piece or if you perform it
With music 2, because you get a score you don't have to listen to the recordings, meaning you can just rush ahead so you have more time for the essay
With melodic dictation, first of all if you haven't already, you should learn to identify intervals (e.g. P4, M3, m6, tritone, etc)
What I suggest doing (this is how I did it), I wrote out the rhythm at the top of the stave on the first playing, then figured out the melody on the next few playings
(you should try to do at least one every second day)
With sight singing you should do a similar thing to melodic dictation
Get a feel for the beat and rhythm, sing it through once or twice, figure out any intervals that you don't know individually, put it all together
(you should try to do at least one every day)
You actually have a huge variety of pieces to choose from. 25 years worth of music for your core topic and depending on your option, there will most probably be a lot of pieces to choose from.
I think the topics are Music of a culture, medieval music (I admit not much to choose from but I know no schools who do this), renaissance music (same as medieval), music 1900-1945 (lots of music for every instruments even if they're arranged for particular instruments), music 1945 to music 25 years ago (again, there is a whole bunch of music here!)
You're doing well in music, so I wouldn't think it would be too much of an atar killer, just try your best, Polish off your pieces and learn sight reading/melodic dictation and you'll be fine