The five-finger rule

Not directly related to debate, but... I recently read Reading Don't Fix No Chevys, by Michael Smith & Jeffrey Wilhelm. I liked a lot of things about the book, as I'm a fan of Mihaly Csikszentmihalyi (that's pronounced "chick-sent-me-high," according to someone I know who knows him), and I appreciate the ways that Smith & Wilhelm link their work to the ideas of "flow" and "optimal challenge." Something that stuck with me from the book was the idea of the "five finger rule." Basically, this is a way for students to identify texts that may be a bit above their reading level- they open a text to a page, and raise a finger every time they encounter a word on that page that they don't know and can't figure out from the context. If they raise five fingers on that page, then the book (or article, or whatever) may be too far above their reading level. This was used in elementary school classes, according to the authors, but could be of some use in the middle grades, as well. When students are doing independent or guided research on current events for debating, they will often encounter texts that are pretty far above their reading level. Of course, we want them to challenge themselves, but we also don't want them to get frustrated and stop reading. Optimal challenge (pretty hard, but not too hard- think of it as a Goldilocks principle) is best. So, the "five finger rule" struck me as a guideline we could give to students to choose texts that are not too challenging. There should be a companion rule to help them select texts that are a little challenging- perhaps a "two finger rule?"