Amazing Sheep - Games, Puzzles & Learning. The cardboard sheep is assembled by slotting the pre-cut pieces together. The completed sheep model is then placed over a small dish (provided) of magic solution. After a couple of hours there will be evidence of growth starting and after a couple of days the sheep will be covered in thick fragile 'woolly' crystals which will last indefinitely, as long as they are not disturbed. Quite astonishing!