Front page: Big picture covering the whole page. Bright, bold and attractive. Maybe just the word 'australia' in big letters. Or some kind of slogan or sentence like 'why not visit australia?' or 'come down under' etc.
Inside page: Contents. Make it as simple as you can. This isn't a book with chapters so people aren't going to want to spend a long time reading what's in the leaflet they're about to read anyway. So make it informal and attractive, like: Read about: Facts about australia (page 1) tourist attractions (page 2) hotels (page 3) wildlife (page 4) famous ozzies (page 5)
^ I just made that up on the spot. You might not want all of those, or you might think of some better ones.
Then just do a page for each of them, with plenty of pictures. Make sure everything you write is positive, and try to make the reader feel like if they don't go where you're telling them to go, or if they don't do what you tell them to do, they won't get the full experience of going to Australia. (Don't worry so much about what you're going to write - if this is for art class you're being marked on your creativity and how well you draw). If I were you I'd pick a theme or a colour scheme or both and keep it consistent on every page, for example a purple and orange border on every page, as well as purple or orange page numbers and headings. Or a different Australian animal in the corner of every page.
Remember the purpose of the text - brochure designed to advertise. Therefore you want to give as much information as possible without boring the reader. Pictures and humour (informality) are a great way to do this

have fun with it!