My school district uses portable buildings to augment the classroom space on various campuses around town. These buildings are moved around each year, depending on where there is a need. When outlining the buildings on a school campus, should I simply ignore these temporary structures?
How to deal with temporary structures is not entirely clear, but as a rule of thumb:
If you cannot or do not want to keep them up to date, then I would not add them.
If you will reliably do so, however, and they are in one place for at least a few months, then mapping them might make sense. Consider applying a special tag, such as building=portable or building=portable_classroom.