Melbourne

The answer depends a lot on who you're applying to, and how they recruit. If you are dealing with a larger organisation or one that hides behind a tier of recruitment agencies, you'll be better off being less upfront as to your lack of experience. AI bots going through applications are looking for buzzwords. If the position description is asking for skills a, b and c - be certain to have those words in your application.

Once you reach a human, the best general advice I can offer is: Explain how you can solve their problem. They have two problems:

1. They need someone to do this job.
2. Recruiting, interviewing, hiring, training/onboarding a person in this job is heaps of work.

You're here to solve problems. Not create problems. If you lack the experience they're looking for, explain how you'll solve their problem anyway. It sounds like you're already doing this a bit, but really focus on it. I don't know anything about the education sector to give you specifics, but I know how employers think - I've been that person hiring people. That person wants someone who wants to be there, will be reliable, and who won't be a problem. Ideally someone who will be around for as long as they need (whether that's long-term or a school year etc). They most especially don't want to be back in this place a few weeks from now because you suck or you were over-qualified and got a better offer a few weeks after being hired.

So yeah - tell them that you don't have experience being a teacher's aid, specifically. But also tell them how that's not really a problem because you have worked with kids before, are studying an education degree, and whatever other skills you bring to the table. That's the sort of stuff they're looking for - and your honesty on the matter of experience will be appreciated.

As to the resume, I'd list employers and expand with dot points under each job anything relevant to the present position.