I would sincerely like to tell them that they have a very rude awakening coming up. Being "looked after" by school teachers and parents is actually a lovely place to be. And, to think that you are finally free of shackles and free to indulge in all the wonderful (?) adult (?) activities revolving mainly about the consumption of alcohol is so far removed from being free and being adult that it's not even on that radar.
This is how you make yourself free and make yourself adult: Do something useful. Help someone. Anyone. Do something kind for anothet human being. Make something. Something for anyone.....a friend, a relative, a neighbour - or someone you don't even know. Offer to help in any way you can. Be a real adult and take responsibility for yourself as a valuable member of the community. Seek out a (paid or non-paying) job. Help a disabled person. Help you mother. Help a friend. Do something together with friends that will add to someone else's pleasure. It doesn't have to be something big like working overseas for a charitable organisation; it can be just mowing someone's lawn, or cooking something for your grandmother. Guess what? Being a kind, helpful person, filling every day with something practical or joyful can give you a better 'high' than booze....and there's no hangover!
"Schoolies" is nothing but a display of stupidity, helped along by indulgent parents too afraid to upset their kid by saying "no", when the kid claims that "everyone else is going/doing it" - whatever.
I live in hope for the day when "Schoolies" is looked back upon as one of the stupidest activities ever.