I've moved on to Grade 4's Reading Comprehension sample questions. Here's a question from the "Content" sample (the whole idea of "Content" as part of reading comprehension seems confusing to me to begin with. Is the idea that they're being tested on content that they should have learned in other areas? In that case, doesn't that passage test something other than reading comprehension?)
This is a passage on Antarctica. One of the questions is the following (I won't clip the passage because this is explicitly a question not really based on the passage, which is part of my point):

5. In the selection, what is the most
likely reason that temperatures are
listed in both Fahrenheit and Celsius?
A Only scientists would normally
read this selection.
B More people can understand the
information.
C The numbers look more
impressive listed this way.
D Celsius temperatures make
Antarctica seem colder.

This question is not testing comprehension, except insofar as background knowledge is part of comprehension. It's testing whether the student knows what the difference is between Fahrenheit and Celsius. I do actually think this is information kids should have been taught by 4th grade, but I also don't think it's information that's taught in Language Arts. It should be taught either in Social Studies or Science (I think I learned it in Science). Keeping in mind once again that Science is not on the EOGs until 5th grade, and that Social Studies doesn't appear on them at all in elementary school, the students in schools that are pushing non-tested subjects aside to do "test prep" (and this is happening all over, but it's much more severe in low income schools, since they tend to have the lowest scores) are increasingly likely not to have encountered this information in school. Again, this is information most middle class kids have by the time they're in grade 4 because they've learned it outside the classroom. (Paradoxically, those kids are more likely to have more science and social studies in the classroom as well). This kind of question is therefore a vicious cycle-"low performing" schools emphasize teaching to the test and teaching tested subjects, kids there are often the ones who are least likely to encounter science/history education outside of school, it turns out that the EOGs in reading test background knowledge, but the very kids who need to be taught this kind of knowledge no longer have access to it at school. Because the schools are too busy prepping for EOGs. It's also the case that this is the kind of thing EOG books and  curricula probably wouldn't tell you to teach or study, because it's not reading related exactly. If the EOGs do test outside knowledge to a certain extent, there needs to be a publication of the kind of outside knowledge that's tested. Otherwise, this just is not a level playing field, folks.