DataWorks has worked with many schools that have expressed interest in obtaining a scientifically-derived list of grade-level appropriate words for students to learn that could specifically improve student achievement. Attached. is just such a list! How and Why These Words Were Selected
For years, educators have been interested in coming up with a list of words children should know. There have been various estimates of the size of vocabulary acquired by an average adult. However, if this vocabulary is to be taught in 12 years of schooling, the number of words needing to be taught per week is excessive. For example, 80,000 words learned over 12 years of schooling would be 186 words per week.
One approach to reduce the number of words is to select base words only. Base words are words from which other words are derived. For example, from the word "farm," derived words would be farmer, farms, farming, etc. If the base word is understood, students would know the derived words from knowledge of prefixes, suffixes, verb tenses, etc.
Starting in the 1930's, various researchers have tried to come up with base word lists. One of the most recent attempts was done by Marzanno et al in 1991 with funding from the Department of Education.
Marzanno's list is described as a list of "school" words since the words were specifically taken from actual textbooks and literature books school children commonly read. In addition, he compiled a second set of 17,000 words taken directly from common standardized tests. Marzanno's combined list of book words and standardized test words came to 30,371 words. These words were then edited to select base words only and ended up as a manageable list of 6,764 words for K to 6th graders. These words were then matched back into the student textbooks and literature books to see in what grade students are exposed to each word in the list.
In addition, each word was checked again against common standardized tests to determine in what grade students would come across each word in a standardized test. DataWorks has taken the Marzanno list and merged in other common and high frequency word lists from other sources such as Fry and Dolch to come up with a master list of words all students should know.
DataWorks also determined an appropriate grade level for each word. The grade level was derived by choosing the earlier grade in which each word occurs whether in books or on standardized tests.
If students were to know these words at the proper grade level, they should have no trouble reading grade-appropriate literature books and textbooks and should also be able to do well on standardized tests.