There are five jars for the children to investigate. Each jar contains a set number of like items such as rubber duckies, stretchy snakes, butterflies, small pebbles, and a large mossy (faux) rock. We set this up along with a couple of clipboards and pens to encourage drawing what they see. This year around, it was more fun to stack the jars as high as they could. Either way, it's all learning!