The textual preview of the dates to be sent to iCal is always visible, on the right-hand side of the SchoolCal Window. Regardless of which Tab you are working with, any changes are immediately reflected in the text field.
This information is always current and accurate, and will help you to make sure you have all the dates correctly categorized before pulling the trigger and clicking Done.
Since it is a text field, you can select any or all of it, then copy and paste into any document you wish. The text editing options available directly inside of SchoolCal are found in the Edit Menu:
Anytime you perform Select All, all of the text inside of the Text Field will be highlighted, and the Copy menu item becomes activated. You can also select portions via standard mouse/cursor controls, also activating the Copy menu item.