I'm now a second year math student at a top uni, and in the summer of my first year, I was a part of a small research team where we proved various new results related to Random Matrix Theory and wrote 2 papers on them. Now those papers are up on arXiv, but it hasn't been accepted to a peer-reviewed journal yet. My question is that when I'm applying for summer research programs etc should I list these as "preprints" on my CV even if they haven't been accepted to a journal yet?
If a publication is either published or accepted at a journal, list it under your "normal" publications - if you want, you can choose the caption "Peer-reviewed publications". If it is not published yet, write "accepted at $JOURNAL", or similar.
If the paper is still under review, or otherwise not published at a peer-reviewed journal, but available as a preprint, list it under "Preprints".