The scary bus 4

Every night, Master Jacques gets up and sits behind his computer like a zombie. He writes stories and reads them to his class during the day. But they are not just any stories! Does Master Jacques really write them himself?

What exactly happens at night? The children have to find out, because increasingly strange things are happening. Do these things have to do with the dark forces from the Other Reality (AW)? Or perhaps with the handwritten copy of The Horror Bus that is in the cupboard at Master Jacques's...