There will probably be an iron available in the class as well, so all is not lost if you have some fold marks. Also you will probably be cutting two layers anyway, so you can have the fabric folded down the center, just as it is on the bolt.
Edited to add - I'm impressed that your teacher recognizes the value of starching your fabric for a log cabin. I don't think I've ever taken a class where the teacher told us to starch in advance.
Last edited by dunster; 03-29-2014 at 08:11 AM.