The polar bear needs to be more smooth as it navigates the platforms - right now user uses the spacebar to jump, needs WASD or arrow controls to move the polar bear and make smooth motion.
I love the game. The theme is very clear and the sounds make it even more engaging.
By smooth motion, do you mean moving the character up with the up key, right with the right key, etc? Moving the character with the keyboard was back in CSD Unit 3 Lesson 16. You learn how to use the counter pattern with the keyboard to move the sprites. Activity #6 has you move the sprite in all 4 directions. Teachers have access to the sample solution. If those are not available to you, try working through the activities to make the bear move.
You can also find tips for making the motion smoother in the activities of Lesson 21. This series of lessons uses the counter pattern with velocity to make the motion more complex.
Hope this helps!