I am giving this rating based on it's usefulness for third grade.
I consider my daughter to have an incredible vocabulary for an 8 year old. She regularly uses 50 cent words in context and correctly. I have never dumbed down my vocabulary for my kids, and it shows.
However, this unit seems to use words that adults I know wouldn't be able to define. For example, "lucious," and "hatchment", just to name two. The alphabetizing and dictionary guideword exercises seem extreme, with complex words to teach basic concepts. Ditto on the synonym/antonym portions.
These lessons are decent, but I just don't feel they are on grade level for my third grader, and I think my fifth grader might even struggle here. They just look/read a bit too much like high school level material, missing the components that might make it fun, and with too much reliance on obscure forms of words my children will never have been (and might never be) exposed to in real life.