Primary schools private or public are pretty much equal, Quakers Hill High School is a normal public school, no matter what school your kids go to, its up to the individual child to who they hang around and socialize with because most public schools have there group of good kids and troublesome kids, so checking who their friends are , is probably more important, school wise good school , good teachers.
Quakers Hill High School is open for years 7-10 only. Afterwards they must go to the senior school which takes students from other areas. I am a high school teacher and I don't like this structure because it disrupts students education and many students may not ever make the transition to senior school. The school itself is good and if you like that idea go for it. Terra Sancta is good as is William Clarke (Kellyville). There is a new public k-12 high school opening up in The Ponds in 2015.
Primary or High? All the primarys are OK. Had a lot of problems at Quakers Hill High but that was 10 yrs ago. Terra Sanctas Ok but only if ur kids are VERY sporty, otherwise no. Seven Hills High was very good.