Plug in your crockpot and turn to low to warm up slowly.
Dump in your dry ingredients, stirring to evenly distribute.
Add the water and oil. Close the lid and switch the heat to high.
Set a timer and check your playdough every 30 minutes, stirring well each time. Our playdough took a little under 2 hours to make.
You will know it's done or close to done when the playdough begins to form a ball when you stir it.
When that happens, remove the stoneware insert from your crockpot and stir some more. Dump it out onto a smooth surface and begin to knead---be careful---it's going to be hot. If your dough is overly sticky, add a bit of cornstarch; if overly dry, add a touch more hot water. Each time you make the dough, the water required will be a bit different, depending on the humidity in the air.
Separate the dough into manageable lumps and push a hole into the center for a few drops of food coloring--let the kids squish the dough around to distribute the desired color. Their hands will be a bit colored for a few hours...