My knowledge about my son's (well my sons') reading level(s) come from the fact that the two boys (5 years apart and annoyingly to the older boy) read many of the same books and then engage in in-depth conversations about the books. In fact, they make me read (or I choose to read) some of the books they read and we have basically what amounts to our own book club meetings in the car or at dinner, led by them.
Also, I still read to them at night and stop and make sure the 9 year old understands words he might not have seen before (and he always already knows them or has figured it out) and stop and ask him to predict what will happen next (we both give our opinion and then see who is closer) and all sorts of comprehension conversations. The boy can comprehend, he can make connections, he can question and theorize, he can find the author's purpose, use context clues, and then use techniques he sees in his reading in his own writing. He can summarize.
He could do this in K reading 3-5th grade level stuff. The first grade teachers gave me the whole "but we need to work on comprehension". I just rolled my eyes. Second grade teacher was where he bloomed because she didn't do the entire "comprehension" line. She got him and recognized his ability.
