A film with a higher speed usually will give a greater depth of field, or broader range of focus, and will illuminate subjects at farther distances. Prepare the equipment for use before you arrive at the site so you do not have to load film with kids and teachers orbiting around you. Install fresh batteries and carry an extra set. If you are using a manual camera, make sure the flash is synched with the shutter speed. The OAC staff likes to have photographs in slide form and color prints.
Slide film is quirky.
It's not as forgiving as color negative film, which means the exposure has to be right on the money. It's also very sensitive to different types of lighting, so using the wrong kind can result in strange colors. During manufacture the film is balanced for daylight scenes or for those lit by tungsten light sources. Daylight balanced film should be used when photographing outdoors or when using a flash. Tungsten film is produced for scenes illuminated by a heated tungsten filament.