Lighting 2

In most scenes, we filmed in dark areas of the school that we had access to. It's assumed almost universally that fear of darkness is the most common fear. Humans have an innate fear of the dark and in darkness is the unknown. That adds to an underlying state of fear for the film to begin with. Add things that you can't see that just pop out and you've got the underlying features of every horror film. Darkness strengthens the effect.
Here are a few instances of where we used dark lighting to create this effect.