Follow these steps

1. Create a water world with 12 ships.
2. Change the color of 11 of the ships to blue and change the remaining ship to red.
3. Use the arrow keys to control the red ship.
4. Use the space bar to allow the red boat to fire missiles.
5. Program the blue ships to move wander quickly.
6. Program the red ship to subtract 1 points if it gets bumped.
7. Program the red boat to add 10 points if a missile hits a blue boat.
8. Program the game to make you a winner if you get 100 points

Ideas that might make your game more fun:

1. Experiment with the missile reload time.
2. Experiment with the waves. If the waves are too high it is very hard to hit the other ships.