Most schools only have scripture which is taught by outsiders once a week. Usually they have Catholic and protestant but different schools may ahve others as well, our school has Bahai, and another school had a jewish class- it depends on the school and their different needs and availiability of someone to teach.
My DD in Year 3 is studying people and their beliefs so they are learning about all the major religions as part of HSIE (Social studies)
Basically, public schools don't teach religion as such.