Open-Access, Club, and Public Goods: The most important part of this section is the definition of each type of good.  Table 16.2 on page 558 is a good way to organize the presentation of the differences.  Asking students for additional examples of each type of good will help reinforce the differences, particularly because many suggestions will bring up possible gray areas in the definitions.  For example, a park can correctly be classified in any of the four categories depending on the specific conditions of the example one has in mind.  Finally, while it is not a concept likely to be misunderstood, the idea of free riding is important enough to merit a little extra attention during lecture and class discussion.