a. Between 1860 and 1991, American publishers produced readers for the same grade at widely divergent LEX levels (e.g., in 1968, first grade readers were available between -68 and -31).
b. The most difficult readers were generally published before 1918. By modern standards, Professor McGuffy’s pre- and post- Civil War readers were very difficult.
c. After World War I, mean reader LEX levels for all grades were generally simplified.
d. After World War II, mean levels of readers for all grades but third became even simpler. These were the books used by the Baby Boomers and successive cohorts.
e. School publishers in Great Britain did not simplify heir first grade readers after World War II, implying that there was no compelling educational reason for American publishers to further simplify their readers.
f. Today’s mean sixth, seventh, and eighth grade readers are simpler than fifth grade readers were before World War II.
g. Sentences were also shortened, from about 20 words before World War II to about 14 words now in Grades 4—8.
h. Texts for grade x + 1 are typically more difficult (lexically) than those for grade x. When the early readers in a series are simplified by a publisher, so too (generally) are the readers for later grades.
American readers were rewritten after World War II for many reasons: to modernize their content and graphics; to incorporate principles from research in education, psychology and linguistics; to emphasize new kinds of social relations; and to respond to television, which was fast becoming an unprecedented rival for students’ attention. Those considerations required that readers be changed but not that they be simplified. Chall (1967) described the justifications given at the time for simplifying schoolbooks; they were to increase their accessibility for students and raise the level of reading success.
The extent of this simplification is notable. Apart from one extraordinarily simple text (LEX = -75), most first graders in the Baby Boom era used readers whose LEX levels were between -53 and -65; that is, on average, first grade readers were 12 LEX units less difficult than the readers used by their parents and grandparents between World Wars I and II and 15 LEX less difficult than the texts used by students in the same grade in Britian — where the students were a year younger in age. Since the empirical range for LEX is about 140 units, a 12 LEX simplification represents 9% of the empirical range. Workbooks are also designed by the same publisher as the readers and are used in conjunction with them. Given the workbooks’ format, we cannot measure their LEX levels. It is unlikely the publishers would make the workbooks harder than their own reader for the same grade level.
In simplifying the readers’ patterns of word choice, the publishers also shortened sentence length (Figure 5). From the fourth grade on, the average sentence length was contracted by about 6 words — this is the equivalent of dropping one to two clauses from every sentence. This reduced the students’ experience in working out the meanings of more complex sentences.
Widespread objections from teachers and parents, and media publicity over the simplified, often dull, Dick, Jane, and Spot-like readers, caused most publishers to acknowledge that they had oversimplified their first and second grade readers. In the 1963 —1991 era, the mean LEX levels for those grades was restored to pre-Worid War II levels — and without ill effects. While they made those early texts harder, the publishers made the fourth, fifth, sixth, seventh, and eighth grade readers even easier — to the point where these are now at their lowest level in American history.
Schoolbook Simplification and Its Relation to the Decline in SAT-Verbal Scores
Donald P. Hayes, Loreen T. Wolfer, Michael F. Wolfe
American Educational Research Journal
Summer 1996, Vol. 33, No. 2, pp. 489-508