previous | start | next

## Example: An Educational Game (CRC Cards)

- First we list the nouns:

  > Player | Clock | Time
  > Level | Game | Round

- Level is just an integer between 1 and 4; it doesn't need a class.
- Start with a simple class: the `Clock` class.
- When a clock draws itself, it must draw the hands to show the current time.
- To get the current time, it must collaborate with the `Time` class.
- How does the clock know what time it is? You need to tell it:

  > Clock
  > draw | `Time`
  > set time |

previous | start | next