Very interested to see where this goes. Overall it's well structured but I am not sure where the child slave labour element comes in. It used to be the case that children were regularly included in volunteer work in construction and food prep at assemblies but I would be surprised if Australia is any different to the UK, US and (AFAIK) Europe in only allowing those over 16 onto sites along with the fact there is no organised food prep any more except for some schools - which kids would rarely if ever be involved in.
I can recall anything in print which encourages the forcible inclusion of children in construction, food or other voluntary activities. Of course some kids are made to do some things like hall cleaning and most have to go on the ministry but I think you'd be hard pressed to count that as child slavery.
Sadly I think that bit undermines the rest of the genuinely strong arguments in the petition.