Each player secretly places his or her four ships on the piece of paper. Ship sizes are as follows: battleship (five circles), cruiser (four circles), destroyer (three circles), and submarine (two circles).
Here's how one student placed her ships.
The first player begins the game by calling out a pair of numbers. For example, (2, 5) would be a miss on the chart above. The player with this chart would call out "miss". Then it would be her turn to guess. It takes five hits to sink a battleship, four to sink a cruiser, etc. The first player to sink all four of the opponent's ships wins. Players may agree on taking more than 1 shot per turn.
To find out what this special relationship is, examine 3-dimensional objects (those listed below and others) and fill in the first 3 columns. Then perform the calculations in column 4 and write your answers in column 5.
What did Leonard Euler (pronounced oiler) discover?
| 3-D objects | Number of Faces | Number of Vertices | Number of Edges | Number of faces + number of vertices - number of edges | Answer |
| cube | |||||
| rectangular prism | |||||
| pyramid | |||||
| triangular prism | |||||
| tetrahedron | |||||