iCal does not require that you enter a Location for your Events, but if you desire to create one, SchoolCal makes it easy. In the text box just above the Done Button, type whatever location information you wish to be associated with your Events. This data becomes part of your User Defaults, and will not change on subsequent launches of SchoolCal until you change or delete it yourself.
The same location will be written for every single Event that SchoolCal generates: First and Last days of school, Vacation Dates, and all dates set up on the Other Dates Tab.