Hang it anywhere
Folds up neatly
The fold area and pockets
Laid flat, you can see the roominess
Here's how I built it. Or how I would, were I not using scraps. The interior fabric needs to be a strong enough fabric to take a beating and hold itself together, in shape. I like the pre-quilted fabric for that, or an upholstery fabric. The exterior and pockets should be a fun fabric. My bag is 12x24ish, though I will make the next 16x28-30". Before sewing, fold the interior fabric in half, and then pin up from the fold 1", this is the bottom of the brief case, and should not have a pocket anywhere in this space.
1st Pocket: Interior fabric only! My strip here is 4-1/2" high and 21" long, with elastic zig-zagged along the top and then hemmed. I laid it on the edge of the interior fabric, pinning it on at the 1/2" mark. Then with a quilt ruler, pinned it down at every 1-1/2", using my thumb (though anything else would also work) inside as a spacing quide, before pinning each 1-1/2" pocket. After pinning, I sewed the individual pocket seams down, leaving a 1/2" at the bottom to fold under. Once all the 'side seams' were in, I folded under the bottom, creating a fold in each individual pocket, and sewed it down. What I learned and what I will do different next time:
1. I should have used a pencil and marked exactly where the top of each pocket should align on the quilted fabric, I will next time to keep it straighter.
2. I will put in two lines of wide stitching along the bottom, to gather the bottom when hemming, rather than folding it.
2nd Pocket: Interior fabric only! This pocket is 9" tall and 15" wide, with an inset zipper. I put the zipper in 2" from the top, hemmed the pocket all the way around 1/4" deep, and then ironed in a one inch double fold all around, matched the sides so that they were all the way to the edge, then sewed it down.
What I learned and what I will do different next time:
1. I will put in two lines of wide stitching along all four sides, to gather the bottom when hemming, rather than folding it.
2. I wont hem first, I will hem as I go, on future projects.
3. I will have to use a pencil and marked exactly where the top and bottom of each gathered seam of the pocket should align on the quilted fabric, to keep it straight.
3rd/Whole side Pocket: Interior fabric only! This pocket is 15" x 15". Learning from the first two, this one has double seam, wide stitch gathering along all four sides. It also has an inset zipper (both zippers are 9"). First, gather the top and the bottom so that they are both flush with the sides of the interior piece. I pinned 1/2" up from the bottom fold for this side (up from the 1" fold taken along the bottom, setting in a 1/4 hem as I went, and stitched it down, then do the same about 1-1/2 inch from the top of that side. Then gather the sides so that they fit the pockets size and stitch them in 1/4-1/2" from the sides, being sure the fabric is flush with the sides of the quilted fabric. Having the binding over all the fabrics (pockets and outside) helps make them stronger and looks neater.
Lay the pocketed side down, and then lay the exterior fabric with the pattern up together, and zig-zag along the edge. This makes it easier to add the binding. The binding goes on next, I used prepackaged here, but usually make my own.
Finally, make two handles of the exterior and pocket fabric by taking 16"x1 or 2" (depends how much fabric you like to fold under) strips, folding under and sewing down along one side. Center (about 4" from each end) the these straps 1 to 1-1/2" into the fabric and sew along the bottom, top and both sides, and then add a couple of X's to be sure that they stay affixed (remember, this is for a child, and they are not known for the delicacy with which they handle things.)