Before beginning any experimentation, its important that students use the correct terminology to discuss what they are experimenting.
Inform the students that the up-arrow port for any z-oriented Stern-Gerlach device is called “spin up in the z direction”, while the down-arrow port is called “spin down in the z direction.” Let the students know the same convention applies for x and y as well.
The corresponding ket notation for each state can also be written on the board if the instructor wishes.