I've Sunk Your Battleship!
Play the game of "Battleship" with a partner. Each person needs his or her own grid of the coordinate plane. Before the game begins, place your ships on your grid; make sure each person chooses 5 ships of varying sizes that each cover between two to five lattice points (the intersections of the grid lines) on the coordinate plane. DO NOT LET YOUR PARTNER SEE WHERE YOUR SHIPS ARE!! When ready, take turns sending a "bomb" in an effort to sink your partner's battleships. Do this by reading off ordered pairs of coordinates where you think your partner may have a ship. Remember, you have to hit all of the lattice points a battleship covers in order to actually sink the whole ship. The first person to lose all of their ships has to surrender to the loss.
An online version of this game can be found at the Math Gym Arcade.
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