DD made this to match her school bag. It measures 8 x 5 1/2" and the spine is 3/4" . We used both timtex and batting. There's a pocket on both the front and back covers.
She wanted to try a narrow binding and had trouble with it. We used clear elastic to secure it in the case. If we make another one, I think we'll change how we attatched it at the bottom, because it covers her headphone jack.