Using the black leotard/sweats you could also use the childs body as the straight part of the note, that way you would only need foam or armature covering for the top and bottom of the note making it a little less expensive. Then glitter the note and the part of the clothes that are "the note". Foam is going to be a little pricey I think, you may be able to get the real thin stuff at a good price, if that is right, you could "thread" wire (floral or similar) through it for stability. If you spray paint the foam make sure you get an acrylic based paint and TEST it b/c some will melt the foam. The other thing that just off the top of my head is you may check out lowes store for some wire product that is shapable but holds it's shape (rebounds like the car shade things) for the shaped area and glue to the edges of the fabric, or the foam summer swimming pool noodle things.