This is the first level of the game. As you can see, students would take their finger and "dig" a hole to allow the water to go down. As students trace the path, the water begins to flow.
This is a much more advanced level. Now we have purple goo. (I have no idea what it is really called.) The purple goo is bad. If one drop gets into the drain, Swampy gets mad. There are also additional challenges. You have to get water to it the containers which act as a switch causing the bridges to move. Once water hits the red container, the red bridge will swing over and over the purple goo. If the goo fills up and hits the blue container, than the blue bridge will open and allow all of the goo out which will go into the drain.