Actually I'm still not sure if I've picked the right school. It's definitely not the best school. It's a convenient school for us as it's walking distance.
So one website that is available is https://www.myschool.edu.au
It says it has an index of community socioeducational advantage (ICSEA). No matter how I read it sounds like socioeconomic status of the school community. So I guess the higher the number the better off the students' families are.
They use the naplan testing here. I don't really know what they test on these tests yet. Apparently some schools are pretty relaxed about this.
We also did the school tours to have a look at school facilities and to meet the principal and to get a feel of the school.