While the layout of the lesson is not very detailed and the link to the PowerPoint is no longer valid, there are some great exercises to examine the role of nitrous oxide in the environment. For middle level learners, the resource listed at the bottom of the lesson plan is a great investigation; if you have computer access for the kids, they could explore this on their own or with partners. Otherwise, it could be projected in class for a whole-group activity. For high schoolers, if you have access to the materials for the field investigation, it could be very powerful. The data nugget handout includes some graphing and data analysis activities.