This is a little late, but I'd figured i'd show some of my progress and concept art before the end of this jam

Day 1:

Because I don't have much programming experience, I didn't want to stray too far from a traditional breakout game.  I decided to reuse some rock and tree art from an old project as "bricks". I ended up liking how they looked, so I decided to go with a nature themed game!

I wanted to add some collectibles and enemies to make it a little less like breakout (while keeping breakout physics), and more like pinball ( having the focus be on interacting with the table). Breaking "bricks" would be more of a means to reach parts of the room and to collect items. I also liked the idea of requiring the player to actively use a "hardening" ability in order to break large objects and defeat enemies.

Testing the breakout physics!

Day 2:

Came up with an extended game concept. It may include more than i'll be able to complete in the time period, but I'll probably continue working on the game after the jam. 

I thought it'd be neat to be able to swap between different "pinballs" with different functionalities. The game would basically have 2 layers: one for the hedgehog, and a higher layer for some type of bird. This could allow for some neat puzzle mechanics between layers, such as buttons, switches, etc. 

I also thought it'd be important to allow the player to launch the ball at a 90 degree angle if caught. Additionally, holding a character in the paddle would enable switching between the two. I'd probably just create two layers by defining different collisions for each ball, rather than creating a Z plane.

Day 3:

I'm writing these in retrospect for now, but here is what I got done on day 3!

I fixed some physics between the ball and paddle (I have Joe to thank for the help!), where the ball's trajectory would always be a set angle. Now, the ball's path can change angles relative position on contact with the paddle. I also added some variance to angles when interacting with trees (which are equivalent to bumpers).

I also added the start and game over screens, lives, points for breaking rocks, and collisions animations for the trees.

(The game should run a little smoother than the gif)

Wow. This looks amazing! Love the sketches and concept! Can't wait to try it out!

Nice,  I think concept art is the key to good design process.