It's just an easy fabric 'sandwich' - I used decobond in the middle and a cute fabric from the same collection on the back, with some of that easy to use Wrights double fold bias tape quilt binding. I think it took me about 3 hours in total to make!
There is a back story to this too. A friend gave me some fun hand me down mats that held together like puzzle pieces, and it would make a little town for Cam to drive his trucks on. Well. It didn't stick together so well, so anytime Cam would play with it, he would run to me and say - Mama! Broke! And I would spend another 10 minutes putting it back together... only for it to come apart again. I tried to duck tape the pieces together, but that was a failure too. So, being the wonderful mom that I am, I threw it away. This panel will be the perfect replacement for that. Plus - totally machine washable, unlike those foam pads.
With the small amount of leftover backing, I made this little drawstring bag to hold some cars: