Finally, your child can play with toilet paper without wreaking havoc on the plumbing! This combination of TP, Ivory soap, and water blends into an amazingly versatile consistency. Younger tots can simply have fun squishing, stomping, and mashing it like mud; with the help of soft-sided cups and other molds, older kids can shape it into towers, castles, and more.

Step 1: Ask your child to help you unravel about 1 1/2 rolls of two-ply toilet paper, then tear it into 2- to 3-square pieces. Put all of the pieces in a plastic tub.

Step 2: Grate half of a 3.1-ounce bar of Ivory soap into the tub.

Step 3: Slowly add about 6 cups of warm water, 1 cup at a time, while you and your child blend the mixture together by hand. It'll take about 15 minutes to mix it all up -- hang in there, it's worth the wait! Stop adding water when your mixture feels creamy and saturated. (You can always add more TP if yours gets too runny.)

Step 4: Help your child mold the mud into mountains, towers, and other shapes. To make the castle shown here, we just packed the concoction into disposable plastic containers (poke a hole in the bottom first so you're not fighting a vacuum effect), then dumped it back out.

Step 5: Store the mud at room temperature in a covered container; it'll last for several weeks. (Dispose of it in the trash.)