Mostly, I think GEs are best ignored. For tests with more than a few questions per level (Explore, ACT), comparing a kid's scores to how older kids score may be worthwhile. For tests with just a few questions at each grade level, it's not very helpful to get a grade result. Schools care about whether a child has mastered the local curriculum, so end-of-year finals are usually better at figuring that out.
I agree. GE are definitely meaningless on a grade level test, and slightly more interesting on an open ended achievement test like the WJ, Peabody achievement, etc. I definitely don't think they mean you could comfortably drop a child into a particular grade in a subject. I know both my kids would cry if I tried that!
