I'd put the full name but write in somewhere "but goes by X". Or, just tell the teachers. I've only ever gone by my nickname (which is a traditional short form of my full name) and I always just told teachers on day 1 to call me that.
I agree with this.
Melinda
Mommy to
The Gift 10/01/05
Elfgirl 5/25/07
Sparky 6/27/09