(I thought you were asking for low-key comps and was very confused)

So, my guess would be that you don't want a Cinderella retelling as a comp (although, if you do, here's a Goodreads list for you), but rather to say "A Cinderella story that is [magical school] meets [contemp book about character competing for scholarship money]." You can easily, IMO, just use Cinderella as a comp (Cinderella meets [magical and/or scholarship contest book]), but that may not give a feeling to the agent for your book.

So part of the problem is that there is no way for us to give a comp that suggests your voice or style or the feeling of the book. We can give plot suggestions, maybe suggest books if we had a good idea of the character, but probably not one that gives your book's feel.

You really should just read a bunch of books in your desired genre. Are you looking for recs or for us to figure out your comps based on our experience. I hesitate to give comps, but am up for giving recs on: magical books, contest books, Cinderella retellings.