As with all countries where a lot of people are immigrants or the children of immigrants, there is a desire to retain some attachments to the old country, primarily through religion and language and culture. When this is overdone, then assimilation is harder, takes longer, and “real Aussies” can get frustrated and feel alienated in their own land.
Schools should be the base for assimilation. All schools should only teach English and have no religious or cultural aspects at all, aside from general learning about all such things.
Schooling can be set so that the core subjects are taught Mon-Thu. Friday becomes an optional day. (Different schools could choose different off days) Children can do their homework (at school or at home), and non-core subjects can have an extra class (staffing might be a problem, unless different schools share teachers and have different off days). These can be days for learning and participating in the arts, school athletics and other sports, and extra tutoring for those who need it.
No student will be required to attend on a Friday, but obviously kids who have parents at work might need to attend anyway.
Here’s the key: for any parent who wants their kids to get a specific language, cultural or religious teaching in a school environment, they can send them, at their own expense, to such a place on Friday.
That way we still have everything the current system has, but with far greater assimilation and less racism.