Hey!
I wanted to share a new USACO training website that I’ve been working on for a couple of months now, which will be helpful for many people here who want to advance in the USACO contests that are coming up soon!
Algo (https://algousaco.com) is a training platform that enables you to solve randomized USACO problems, track your progress, take mock contests, view your analytics, and more- all in a much better UI than https://train.usaco.org. You can even mark problems as unsolved and get back to them later. There’s more information at https://algousaco.com/about.
Algo has over 10k page views and over 1.2k users from 46 countries worldwide and is also entirely free. 
Let me know what you think!