The objective of the field trip reports is to link the real world with the academic exercise of learning geography. You will use these reports to assemble a Neighborhood Portfolio, examining that same place in depth from some more perspectives. So, pick a place near where you live or work to make it easy to you. At the same time pick a place that is large enough to have a center (like a town, or part of a town even) where people congregate a bit and which displays diversity of people.
Define your particular area. Make it large enough so that it will be easy to find information online but not too large. For example, Washington DC would be too large an area but Georgetown may be useful. Use Google Earth and make a screen shot so I get a sense of how large the area is and where it is located.