Aside from the gruesomeness, which I agree is extreme, having kids that young spending several days writing stories from memory is not developmentally appropriate, even for many gifted kids. And it is not developing the "higher order thinking skills" that most gifted programs are tasked with developing. In Bloom's taxonomy terms, it is at the bottom (recall) made more (inappropriately) difficult with the writing skills overlay. I'd definitely talk to the teacher and the principal if the teacher wasn't receptive to my concerns.