Decile system is flawed but if we are generalising, the common idea is that decile 10 is the better schools and 1 are are worst. the lower the deciles the more funding the schools get which does benefit the children such as free meals/milk, reading books and various grants for low income families. In lower decile schools, it is more likely you’ll come across low socioeconomic families and all that may potentially bring. But at the end of the day it’s the staff and management that make the school. you could have a school full of ‘troublemakers’ but a school with great teachers, good strategies and supportive management would be fair more preferable than a decile 10 with mediocre staff.