I'm glad people like you make game jams specifically for Scratch. I enjoy coding with Scratch, and even had my project featured on the front page one time! Good luck to everyone participating in this jam!
https://scratch.mit.edu/projects/724032834 Puzzle game about trains. It continued to grow and now has a fanbase, level editor, and texture packs. Also, I enjoy using scratch for a similar reason! Most people think Scratch is easier, but it's actually harder. Every time, we need to start... from scratch. No platforming engine, no particle effects, no 3d ANYTHING-- but brilliant people pull off making something groundbreaking.
That's why pretty much all of the games look the same. Everyone just follows a tutorial, and it has the same result. That's why I pride myself in following tutorials as little as possible. I've made a particle system, a platforming engine, a dialogue engine, and a topdown RPG engine. 3D scares me though.