There’s no recipe, just cornstarch and water. I added liquid watercolor paint to the water, and placed the pitchers of water and bowls of cornstarch in the sensory table for the children to discover.
At the end of the day, it was time to leave the goop to dry out again. By the next day, it had dried into a thick, chalklike sheet, which crumbled easily into large and small pieces that could be scooped and spooned.
But, what is dry can be made wet again, so it was time for more pitchers of colored water.
Once everything was mixed together, it was too watery, so it I refilled the bowls of cornstarch.
And, once more, the mixture dried out again. All ready to be made wet again the next day.
Note: If you want to try this yourself, here are some tips. 1) If the goop is very wet at the end of the day, drain off excess water before leaving it to dry. 2) Be sure to leave the sensory table uncovered. If you have to cover it, use a light sheet and leave it vented on the sides so air can get through. 3) The drying process doesn’t work as well in humid weather. 4) If your goop starts to smell bad, or has black specks in it, it’s time to throw it out, sanitize the sensory table, and start again with a new batch.