This is one in a series on distance measurements, covering the Standard System. Others in the series are on quantity, metric system, weights, time, and area. It looks like the intent was to provide a definition on one side of the spread, and a concrete example on the other. The first concrete example was clear (7 inches between two toys), because the illustration showed it very well (a ruler). But for most others after that, the example was not borne out in the illustration, and thus not made concrete. For example, on the 'yards' page, the example was a football player running 15 yards. The illustration only shows a football player standing there smiling. If the intent is to teach, then the example pages don't really work. If the intent is to provide a teacher with something to talk about and teach, then maybe okay. There was no illustrator. A production designer (who did pretty good work given some clear constraints), used stock photos only for all the illustration.
As with many books, I'm wondering why we need to spend money on hard cover, four-color printing, and paper copy when all these measurement facts are readily available? The argument from the series editors would likely be 'reading level'. This book is intended to be readable by transitional readers, who have more or less figured out how English words and sentences work, and are becoming more fluent at reading orally and silently.
The measurement aspect of this series addresses clearly the content standards endorsed by NCTM. The series is also explicitly linked to the "Five Pillars" approach to literacy, which is research based but is also an inadequate view of literacy. The past ten years of research have borne out how impoverished the "Reading First" view of literacy is and even the damage it can do to school programs. The five pillars approach was an active effort to ignore key aspects of the psychology of reading such as motivation, which were found as vital in the NRP meta-analysis, but were not presented to teachers in the digested versions of the research study.