Martha Stewart has a great idea for pop-up sponges, but unfortunately doesn't provide a template. Luckily there's a ton of stencil sites with templates online. You can also have kids create and cut their own designs using flat sponge material.
ABC stencils here:
http://www.bing.com/images/search?q=abc+stencils&qpvt=abc+stencils&FORM=IGRE
Crafts by mommy has a fun way to re-purpose colorful kitchen sponges, simply cut the sponge into strips and tie together with dental floss.
Get the instructions here:
http://craftsbymommy.blogspot.com/2011/02/easy-bath-toys.html
Passion for savings has the kids use the sponges for a gun game of Bozo Buckets.
Get the instructions here:
http://www.passionforsavings.com/2013/05/how-to-make-your-own-sponge-ball-toss/
Mom endeavors uses different textured sponges.
Get the instructions here:
http://www.momendeavors.com/2011/07/diy-splash-balls-2.html
Cheryl style makes a game for the sponge balls with frisbees by having the kids throw them into the frisbees to earn points.
Get the instructions here:
http://www.cherylstyle.com/showcase/diy-sponge-ball-pool-game/
