I would not for one minute let my 8 year old son fly in said aircraft under that arrangement.
I would also voice my concerns to the other parents.
I would also advise the school of your displeasure of the arrangement.
I also would also consider contacting CASA and advising them of the details of the arrangement. If they have nothing to hide, then it won’t be an issue!
Too harsh? Probably not, but better to be safe than sorry.
I so wonder how cost sharing works when the pilot takes up say 10 plane loads of kids??? Sounds like someone with a PPL running a holiday farm for kids wanting to give them a thrill in his 172.
My children only fly with a pilot with gold bars, in a registered charter operation or flying school or with someone I trust implicitly.