I can't really summarize this in a way that'll give justice to how amazing the experience was, but I just got back from a 10-day hackathon with 41 other high schoolers on a train across America.

Among other things, I built a music app similar to Spotify but with a radio-like twist of having a shared audio stream. I enjoyed meeting other like-minded programmers, making friends, and meeting awesome people from Vercel and GitHub.