I'm not sure when your cake is due but I recommend ordering the Boxes and Bows by Sharon Z (SugarShack) at www.sugaredproductions.com
She teaches you various ways to do different boxes and they're all great depending on the look you want.
If you look in my pics, I did a wine bottle in a crate. To date it's one of the easiest cakes I ever did using that DVD as a guide. You could use the same idea for the toy box. And the cake is just a double layer sheet cake.