I was talking to a good friend about this the other day, and we were unable to fully conclude the answer.

Being a british colony for so long, is schooling in HK primarily in cantonese, mandarin or english?

and what was/is the official language?

Schooling is mainly in Cantonese. They do also learn English as well but it is predominately in Cantonese.

....unless your talking about international schools which are mostly English.....

Having once been a British colony, HK education diplomas hold a lot more weight here in Australia than those gained on the mainland.

Nurses who gained their qualifications under the HK system, for example, are recognised here and much sort after for migration where as those who got there diploma under the Chinese system are not.

It's fucked up.
That's why the system is horrible.
They changed from Chinese to English to Chinese back to English...
I don't even know what it's in now.

The education system is fucked up.

Official language used to be English (obviously), but at this time HK is a dual-language system.  Official documents are bilingual, and the parties to a contract can choose which language to write contracts or litigate in.  

For education, it's been primarily Chinese for a very long time even way before the handover, simply because of the huge number of Chinese-speaking parents whose kids don't speak English.  Interestingly, a large number of native Chinese speaking parents artificially speak English at home in order to give their kid more practice.  Schools using English as the primary medium of teaching are popular, and tend to be expensive, but are definitely in the minority.  

There was a political move a few years ago to LIMIT the number of places at English-speaking schools, in deference to the PRC Gods, and to force many schools to switch from an English medium of teaching to a Chinese one.  There was such a storm of protest from parents they backed off and increased the number that are allowed to teach in English - but it's still a minority.  

Interestingly, even the English Schools Foundation, which is required by law to teach in English to English-speaking kids, is under immense pressure to increase the proportion of its teaching that is in Mandarin Chinese ... a clear indication of the direction things are moving.  My guess is at some time English will become an "optional" second language with Chinese taking clear priority ... but at this time Hong Kong wants to be seen as an attractive place for international investors to come to.  English remains important for both civic and educational purposes, in spite of it being a clear minority.

Not to mention status too. The ability to speak English is seen as higher in the social hierarchy. We know how Hong konger are very status conscious.

It all sounds very confusing!

What I wanted to know i guess is, ok, students say in early age will go to school, so parents get to choose which school?

I ask, because i know the language your taught from a young age is usually your primary language, and some of my friends told me that alot of them had some trouble with english only while they were over there

Education system is so wrong in HK. Kids spend all their time at school or some learning centre, maybe in some cases leaving home at 6-7AM and getting home 7-8PM.

Why confusing?  

Yes, parents have SOME degree of choice over which school.  Admission to a school is determined by three factors:-
  1. Where you live, do you live within their "catchment area".  Some schools are so full they only take kids who live nearby, regardless of how much money you have.  
  2. Budget.  Money talks.  You can buy your way into the most prestigious schools, but it may cost you up to $2-3 mio to do so.  If you don't have money, you're very limited in only choosing from locally-available government-funded or subsidised schools.  
  3. Academic ability.  Schools pick smart kids first because their results make the school look better.  

Those are the constraints that parents face, and the limitations they face in choosing a school.  

Within those constraints, parents DO excercise their preference and choice, in particular they may choose based on
  Language of instruction
  Religious background
  Reputation
  "Band" - the quality of schools is assessed according to Band 1 / Band 2 / Band 3, pretty much defining price vs quality.  

The 4th factor you're asking about - native language - is not a big issue for young kids, but it does start to matter over about 6yo, when reading and writing start to be an important medium of education.  

In Hong Kong a LOT of parents then go on to supplement the basic (statutorily mandated) education with extra-curricular activities: extra math, extra language, music, arts, dance, etc.  You only have to walk a short way in any residential area to see many many private Tuition Centres, including some big-name brands like Kumon.  HK parents still have a memory of what it's like to be a refugee (either themselves or their parents) and they are very competitive about educational achievement and academic results.  

It's ironic that they push their kids so hard, chasing precisely the dream that their kids should have an easier life than they themselves are having ...

What that means is there's a lot of pressure both in school and outside school to learn fast, including language.  It's a no-win situation, since learning a language is primarily a matter of exposure to that language, building both fluency and vocabulary.  Kids who put a high priority on English ability will learn less Chinese, and kids who put a high emphasis on Chinese will learn less English.  For example I know a number of Chinese guys who speak fluently but can't write, because they were immersed in an English teaching environment.  

Generally speaking there are two phases to language learning:-
  before 7 years old
  after 7 years old

It's been shown that people who learn a language (any number of languages) before their teeth start falling out use a different part of the brain compared to languages the learned after their teeth fell out.  This means young kids do have a natural ability to learn languages which is lost later on.  Nothing to do with parental choice or the education system, young kids just absorb languages naturally whenever they hear them.  Later, if you stop being exposed to a language, your ability sticks at that level (you may get rusty but you don't lose what you learned and it soon comes back when needed).  When you return to that language environment (country / school / social group / etc.) you start learning again.  

So if your friend is having difficulty with English, all that means is the people around them worked harder at English than they did, and they're in catch-up mode.  Very probably, your friend will have learned something else that his peers did not learn.  All the time his peers were studying English, he was (obviously) doing something else and learned from whatever it was he was doing.

Conclusion: Different parents approach the question of language learning differently, and in Hong Kong they do have a lot of choice.  Whatever their choice, it will be a compromise, partially sacrificing ability in one language or academic area in order to invest more time (and money) in another.  In Hong Kong they do have a very wide influence, including home-learning, private tuition, and choice of school.  As a result the precise blend of % English vs % Chinese vs % academics is a highly individual choice, based primarily on the parents' economic circumstances and their personal prejudices.  

What was your question again??

Dartagnan, you misunderstood my confusion.

The difficulty was being from Aus, my friends were  finding getting around, buying things etc abit hard because they could only converse in english.  Possibly due to where they were, but they said that cantonese seemed to be the only language they could converse in.

as to the other bit, Im a native speaker in english, and am learning french.  Im part french, and have been immersed in it because one half of my family speaks it, so I can understand it.  However being based in Aus, we read and speak english, so its my main language.  The country speaks english!  My difficulty arises from speaking and actually reading/writing french, even though I can understand it quite well.

Ok, moving on from that, because HK was a british colony, and being bilingual in engish and cantonese, I wanted to know, the "main" language, ie what is the country's main spoken and written language so to speak.

The system here in Australia is almost exactly the same, without the emphasis on learning a foreign language and probably not as competitive.

Without going into too much detail. I have a good friend whom I met when I was living in Kunming, he wanted his son to have mandarin as a 1st language, said mandarin was a very difficult language to pick up later and kids, particularly boys, who learned english 1st, usually didn't want to study mandarin later. His solution was for his son to spend his first 5 years in the Chinese pre-school system.

He now speaks fluent mandarin and is being enrolled in an Australian primary school next year.

Yeah, Cantonese is the main language.  

English is a distant second, but is sufficient to get by and live a good life if you don't speak Cantonese.