> i wonder what the point of presenting these inventions as your own are

Because if you independently invented it then it is your own.

The value to the student is not necessarily that the idea is novel to everyone else but that is novel to her. And of course the process of invention and development is something that many people never experience, and is valuable in itself.

I suspect she was pushed along by adults, with particular motives, more than anything.

Regardless, nobody involved is honest, and I suspect the honest ones were told the be quiet.