The book itself is felt rectangles folded in half and sewn around the raw edges--one layer was too flimsy. Then I punched 2 holes on each page and put in eyelets (grommets) in and bound it all with binder rings. This all happens, of course, at the very end.
Cover: I just cut out a Batman symbol (freehand, mind you) and hot glued it on.
Page 1: I cut out a little bat cave and sewed jagged lines on it in white. I sewed only the top of it to the page so it could lift. Underneath I sewed a little pouch to hold the Batman finger puppet. I can't even tell you how I made him, but there was a bit of trial and error, cutting, gluing, and sewing involved.
Page 2: Cut out a bunch of shapes and glued them together. Except the vest which I stitched buttons on and sewed to the book, only at the sides. I also stitched on Robin's little smirk.
Page 3: I cut out 2 of each shape and letters just for the top ones. The bottom shapes are glued onto the book and the top ones are sewn to ribbons that are sewn to the book. I put Velcro on all the pieces so they can be matched up.
Page 4: I cut out a speech bubble and added strips of Velcro then sewed it onto the book. I wanted to find little Velcro letters (remember when they use to make t-shirts with them?!) but to no avail. So I finally settled for writing out every letter of the alphabet a few times in sharpie onto a strip of Velcro and cutting it up. There's a little bag in the book that holds them all. Then the kid can write out whatever he wants!
Page 5: I cut out all the shapes, glued them together, and put a little rope underneath the Joker before gluing him down to the book.
Page 6: I made the Batmobile from sparkly felt and sewed a little loop on the back. Then I threaded ribbon through the loop before sewing it at the corners of the page so the car slides back and forth.
Page 7: Pretty self explanatory. I traced the shapes of the pieces on the page of the book, so it wouldn't be too hard to put together, but it doesn't look very nice. I also made a little pouch for all the puzzle pieces.
Page 8: I cut two circles and two silhouettes (copied from Harvey Dent's actual coin, because I'm legit)--one in black and one in silver. Then I hand stitched around the face and all the details. I then sandwiched a piece of elastic between the two before sewing them together. I sewed the elastic to the book, so you can pull the coin and "flip" it. You can't tell from the way the picture's cropped, but I also stitched some scratches on the burnt side of the coin.
If I had a lot more free time it would have turned out a bit nicer and included hand-stitched directions on each page, but it turned out pretty cute and I'm happy with all the fun ideas I came up with!