The canvases were made using this tutorial. I did the stars differently than she did. We put glow in the dark paint on the canvas first, then we temporarily glued stars on the canvas, spray painted it black, took the stars off. I didn't take pictures because I didn't think it would work but it was super easy and worked great! I suppose you could always just finish up with glow in the dark paint splatters for the same effect. (I used Elmer's spray glue that will do a temporary or permanent bond. The stars were the multi-colored foil type ones you can buy anywhere.)
this tutorial. I'm planning on putting fabric on the middle of these using starch unless she changes her mind. (I doubt it. sigh.) If you're like us and have never cut crown molding, you may find this video helpful. We nailed the cornice but glued the molding to the board. Nailing was a pain and caused a lot of problems. The glue holds just as well. You'll just have to do things in steps so the glue has time to dry. We just used wood glue but there may be something out there that will work better.
For the scarf (had to girly it up some) I just used some wooden tiebacks from the curtain section. You can use pretty much anything that can screw into the wall and stick out enough to drape something over it.
Here are the other two cornices along with the Star Wars cookie jars Walmart had at Christmas. The paint is just blue paint that matches the blue fabric. I just brushed a coat on in straight lines. It sure beat doing three coats of paint and it looks really cool!
I have a few more ideas that I might add later (after she gets that room cleaned!). I'm thinking about shelves to hold some of the Star Wars Lego creations as well as something involving an air plant thingy. Be sure to return for the update! If you need more ideas, I've pinned a bunch of stuff to my "Kids Decor Ideas" board.