REL Report: The Impact of Word Knowledge Instruction on Literacy Outcomes in Grade 5

In Florida, the grade 5 English language arts curriculum includes complex text. To be successful, students must have a deep knowledge of multisyllabic words in informational texts. Therefore, district leaders in a large school district in central Florida wanted to examine the efficacy of a new curriculum designed to enhance the word knowledge of grade 5 students and improve their reading achievement. Consisting of 15-minute lessons taught 4 days a week for 20 weeks, the Word Knowledge Instruction (WKI) curriculum covers 20 prefixes and suffixes that address state standards.

REL Southeast tested the impact of WKI and found that it had a positive effect on student ability to correctly extract and spell a base word from a derived word, one of the skills explicitly taught by WKI. However, WKI had no effect on two other related reading skills that were not directly taught by WKI (student ability to select a nonword that best fits the grammatical context of a sentence or to use knowledge of word parts to infer meaning of new words) or on student vocabulary or reading scores.

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 The Institute of Education Sciences, a part of the U.S. Department of Education, is the nation’s leading source for rigorous, independent education research, evaluation and statistics