very surprised this project is still releasing problems weekly - I remember this being up when I was in high school. maybe I'll pick it up again since I only did the first ~30 or so back then.

Not only are they still releasing problems weekly, they have a long backlog of problems waiting for release. I submitted a problem back in April 2024, and it didn't get published until October 2025 (problem 963). There's an excellent core development team that works with problem-submitters to get problems tuned up for Project Euler.