# Co-ordinates Battleship: Revisited

I have blogged before about using “Co-ordinates Battleship” to give my students some practice plotting points and shapes on a co-ordinate plane. I’m using the game again this year and now that I’ve figured out a set of rules that seems to work well, I thought I would write it up here.

• Each student gets a sheet of 1 cm grid paper
• I get the grid paper (and lots of other blackline masters here)
• Each student sets up a 15 x 15 grid and labels the x and y axes
• I have students use Quadrant 1 only, but students with experience with positive and integers could use all four quadrants
• Each student has to plot 5 “ships” on the grid:
• one 1×1 rectangle
• one 1×3 rectangle
• one 1×5 rectangle
• one 2×3 rectangle
• one 2×4 rectangle
• Students play in pairs, sitting opposite each other with a binder or textbook propped up between them to conceal their grid
• Each player takes turns sending “torpedoes” by naming a specific point using the point’s co-ordinates.
• If that point is a vertex or falls on an edge or in the middle of one of the “ships”, it counts as a “hit”; if the point falls outside of any of the “ships” then it is a “miss”
• In order to sink each ship, it has to be hit a specific number of times:
• the 1×1 rectangle has to be hit on 1 point
• the 1×3 rectangle has to be hit on 2 different points
• the 1×5 rectangle has to be hit on 3 different points
• the 2×3 rectangle has to be hit on 3 different points
• the 2×4 rectangle has to be hit on 4 different points
• The game continues until one player has sunk all five of their opponent’s ships

Some of the variations and extensions that I have tried or imagined include:

• allowing students to do a transformation (rotation, reflection or translation) at one point in the game, provided that they tell their opponent what transformation they have done
• using a larger grid and/or more shapes
• having students continue their game outside of class using phone, text or e-mail