This is a great concept for the jam! In the brainstorming section one of my suggestions was something similar with scaling objects on each axis individually, but we ended up with something else. I really liked the subtle juice in the main menu, the buttons growing and having a nice small sound effect when pressed.
Puzzle games are hard to do and balance on a small timeframe, especially when the gimmick is this powerful. I liked this game a lot, but I had some trouble with puzzle 3, the boulder. I was surprised the boulder could be scaled at all, but when I tried it could only barely be scaled. I also tried unselecting the boulder and I couldn't so I think it might have been bugged. I tried to scale the player because you could in a previous puzzle, but no go. The solution I found was just hugging the outside wall and I could walk right around it, but I assume that's not the solution you intended.
If you continue this game, I'd see about keeping the rules consistent between all puzzles. That may involve not being able to scale the player character however since that'd be really powerful. Being able to select the character in some puzzles but not others preserves the individual puzzles, but it might frustrate the player because the rules are changing. It made me happy that you could scale the object to a negative value as well, I'd toy with that for a puzzle! Maybe you have to invert an axis to create an opening or something.
Excellent job!