Apart from English, Australian schools mainly teach Indonesian, Japanese, Italian, French, German, Mandarin and Korean . The Australian government is pushing for more schools to teach Mandarin, but from my experience, Australian students don't see learning a foreign language as being important. There is also a shortage of qualified Mandarin teachers.
However students can attend Saturday language schools and learn any language, for example Russian or Arabic. Migrant communities also teach their native languages on the weekends.