The second day of class included graph theory and four color theorem, Euler paths and circuits, as well as Hamilton's Path.

The students were chalenged to connect three house to three utility companys without any intersecting lines. Students were suprised to find out that the challenge was actually impossibe. Students were then given another challenge to color a picture and to use as may colors as possible with no one color bordering the same color.

Graph theory is an abstract idea that allowed for students to draw figure without picking up their pencils and determine whether it is a circuit or a path.