Not exactly sure whether you're looking for game design resources, art resources or "follow" along tutorials for games besides Platformers?
C3 can handle most games without a doubt, but it sounds like the student is ready to actually plan out a more fleshed out game. The next step would be creating a Game Design Document. Breaking down exactly how she'd like the game to be played from the look, game mechanics, start/end, GUI, etc! There's a ton of resources online for game design and they are all universaly applied to all game engines.
Once the GDD is established, then figuring out how to make "XYZ" in C3 will be a lot easier as you'll have an idea of what to search for on the forums/tutorials/google exactly. Just be sure to really break down the GDD in how she'd like each step of the game to be played out. ex. What will the controls be? What animations? What type of Puzzles? What kind of action?
Alternatively! Have her re-create some of her favorite mechanics or scenes from any of her favorite games. Copying is a great way to learn, and again gives you a point of reference when learning C3 and searching for something specific. How was THAT specific mechanic / scene in Florence created? Once it's broken down into bite size chunks you'll see how easy C3 really is when making most 2D games.