is there some link to official information regarding this issue? I'm dealing with the same 'problem' at the moment.
As it stands - teaching is VAT-exempt. However, training (that isn't pure language teaching) may or may not be - you need to clarify with whoever keeps your books as to whether it is. Mine regards it as being exempt, but others may have a different opinion.
in Poland the VAT kicks in more or less immediately as far as I am aware. if you have a Sp zoo there is no VAT threashold
Not true in the slightest - compulsory VAT registration (and payment) only kicks in with a very limited amount of PKD codes, mainly related to consultancy. But anyway, as for teaching, it's VAT-exempt. This might change after the election (in fact, I'm certain it will) - but for now, there's no issue. And anyway, what self employed teacher is going to take home more than 150,000zl a year?
Is having private students in Poland legal or do you have to register yourself as self employed and set up your own company so to speak? I'm sure many natives have them but what about paying tax etc on your earnings? Is it risky to have them? and what are the chances of getting in to trouble with the law if you just accept cash in hand?
Depends on whether you want to risk the Urzad Skarbowy finding out or not. Bear in mind that the tax law in Poland allows them to make assumptions as to your income - you might find that if you get caught, they just 'assume' you've had x amount of classes at y price and nail you for the tax (plus 100% of the total tax owed in fines).
All up to you - the law says you should register and declare the income.
(and a few vaguely hinted at quitting if I was going to be naming them in receipts).
I used to just give them a stamped receipt - no need to name them (or even keep records of their names).