Very cool!
This is a really clever little animation. Moving around your desk through different objects (multiple post-its, rulers, erasers, etc) really separated this from other hand-drawn animations on Newgrounds (of which there are few) and helped to sort of break the fourth wall.
Erasing every frame is sort of a pain and looks a tiny bit sloppy, although I honestly think it added a little to the overall animation. If you want to do this cleaner in the future, get a pad of acetate. It's clear plastic sheets that you can write on with Sharpies and other markers like that. You can get acetate at most art supply stores; I think it's like 10 bucks a pad. A little expense, but I'm sure it would improve your work :)
Visuals and audio synced really well in this video. The sound was kind of low quality, but I can see the file size is pretty big and you probably couldn't upgrade it with NG's file size constraints.
Congratulations on making a really solid bit of animation. This seems pretty likely to win an award, which it really does deserve. Hope your next piece is even more detailed and fun to watch!