oasfree, I am stunned that you are making some rather remarkable generalisations and assumptions with little evidence to back them up. Just to name a few:
oasfree said:
Public primary schools don't teach any difficult mathematics.
This is not true for every public primary school. It all depends on the cohort and teachers. In many public schools students are taught algebra in Year 5 and 6. In my primary school, we even got up to solving problems by setting up algebraic equations (which is meant to be reserved for Year 7).
oasfree said:
Educational courses take in the lowest UAIs date back from the 80s when it was actually under 50%! The students at that time often did not learn any subject (at University) that they were going to teach later. For example, they could become a math teacher even though they failed their maths at HS badly ( and therefore allowed to do math in University).
Those who take an education course in university learn the subject at uni. If they fail maths at high school, then there is a good chance they will fail at uni maths and therefore be unable to attain the degree. What makes a good teacher is not always his or her knowledge of the subject but more his or her ability to interact with students and encourage them learn. You can have a 100 UAI and know the subject you are teaching back to front, but if you cannot interact successfully with students then you fail as a teacher.
oasfree said:
Still those who are not smart enough will eventually fail to perform well before reaching year 10 and would be told to move back to their normal schools.
Definitely not true. It would be very irresponsible for any school to attempt to kick out bottom students. I failed 3 subjects way back in Year 7, but the school didn't tell me to move, they put me into these study skills programs to encourage improvement. Since then, I've bounced back into the top half of the cohort from the bottom for all those subjects.
oasfree said:
So I do believe that some kids in selective schools outside the top 5 are dumb arses.
There are always kids who are "dumb arses" in EVERY school, even in Ruse. I know a girl who went to Ruse and did not get a single band 6 in her HSC. There are kids in Ruse who are several standard deviations below the mean mark. One of my cousins went to Hornsby Girls and she also did not get a single band 6 in any subject. I daresay she didn't even get over 90 in UAI. Ever wondered why Ruse boasts about its MEDIAN UAI and not it's MEAN UAI? Because the median is not affected by "dumb" outliers as opposed to the mean. To illustrate, you can have some score distribution like 60,98,99,99,100 with a median UAI of 99, but a mean UAI of 91.2.
oasfree said:
True for most schools, but when it comes to top 5 schools in Sydney, it's pretty reliable as they have very strong standards. Their HSC trials match very closely with the real HSC.
This is definitely false. Have you ever looked at their trial papers? Some of them are actually EASIER than the real HSC. They also vary from year to year. For example, Ruse's Maths Ext2 papers are often way easier than the actual HSC questions. Several people manage equal first with full marks in those trial exams, yet no-one can pull off full marks in the real thing.
You seem to be under the impression that there is this heavenly glow around selective schools where they have the best teachers, best resources and the best students. Anyone who has actually been to a selective school (like myself) will tell you this is simply false. Selective schools are the same as an any public school with the mix of crap teachers and crap students. The only difference is that selective schools tend to have a higher ratio of academically able students in the same environment. That is the ONLY difference, nothing more.