Instructions
The instructions for this version of the game are the same as for the previous game but the
numbers on the ships are now in ascending order. Explain this to the children before they
start.
1. Organise yourselves into pairs. One of you has sheet 2A, the other sheet 2B. Don’t show
your sheet to your partner!
2. Both of you circle one battleship on the top line of your game sheet and tell your partner
its number.
3. Now take turns to guess where your partner’s ship is. (You say the letter name of a ship
and your partner tells you the number of the ship at that letter.)
4. How many shots does it take to locate your partner’s ship? This is your score for the
game.
Follow Up Discussion
1. What were the scores?
2. What strategy did the low scorers use?
3. Which ship should you choose first? (The one in the middle tells you which half of the
line the chosen ship must be in.) Which location would you choose next? (Again the best
strategy is always to choose the middle ship of the section that must have the selected
ship.)
4. If this strategy is applied how many shots will it take to find a ship? (Five at most).
This method is called ‘binary search’, because it divides the problem into two parts.