Oh, by the way. One reason they don't like for children to select books above their reading level is because they pass challenge and move into "frustration". The frustration level can impede reading and cause a child to stop reading.
And from personal experience as both an early reader myself and the parent of an advanced young reader, sometimes when the child reads above their level they do not check pronunciation of words and their inner voice comes up with a phonic that's incorrect. This has happened with my daughter when a series books that has words that do not obey phonics (maybe words with a French origin). There was a particular word that it took forever to relearn pronunciation of because her reading it her own way repeatedly over the course of a book imprinted an incorrect pronunciation. This happened to me as a child as well. We sort of solved this on our own by getting her a kindle. She can now tap a word she doesn't recognize and we encourage her to do so.
