So here's what you need:
2-3 yards of felt (you can buy this on the bolt at JoAnn's. Don't forget your coupon!)
2 pieces of foam board (I bought mine in a 2 pack, again worth bringing a coupon.)
First I laid out my felt and tucked a piece of foam board into the fabric.
I lined up a second piece inside, then cut the felt so that it would overlap about 3/4" with the other side. I then trimmed the top to leave about an inch seam allowance on both the top and bottom.
Slide out the foam board and pin the pieces in place.
Sew the top seam and sew down the middle.
Slide the pieces of foam back inside the pockets.
Here's where it gets tricky. Sew a seam along the bottom, keeping your sewing machine pedal tightly against the foam board and holding the material tightly together. Trim off excess fabric.
Ta da! You're done!
I recommend adding a ribbon to hold the two sides together if you plan to use this on a wood or tile floor. On carpeting it stands up fine, but otherwise it slips all over the place!
I need to take pictures of the felt board activites I've made so far, so I'll share those in another post. Happy crafting - and playing!