Executive function in the classroom: Cognitive flexibility supports reading fluency for typical readers and teacher-identified low-achieving readers

•Fluency is significantly correlated with reading specific cognitive flexibility.•Cognitive flexibility contributes to fluency over automatic decoding and verbal skill.•Flexibility also adds uniquely to fluency beyond nonverbal and comprehension skills.•Low achieving readers are lower in cognitive flexibility than peers.•Training cognitive flexibility improves reading fluency for low achieving students. Dominant explanations of reading fluency indicate automatic phonological decoding frees mental resources for processing meaning. However, decoding automaticity does not guarantee attention to meaning. Recent neurocognitive work suggests executive functioning (EF) may contribute to fluency beyond decoding automaticity. Two studies examined contributions of an understudied EF, cognitive flexibility, to fluent reading and tested a teacher-administered EF intervention to improve fluency in teacher-identified low-achieving (LA) readers. Study 1 assessed word reading fluency, automatic decoding, reading comprehension, verbal and nonverbal ability, and reading-specific and domain-general cognitive flexibility in 50 1st and 2nd grade typically-developing (TD) readers. Study 2 compared TD and LA readers’ cognitive flexibility and examined effectiveness of cognitive flexibility intervention for improving fluency in 33 LA 2nd and 3rd graders. Reading-specific flexibility contributed to fluency beyond automatic decoding and all other control variables in TD readers who had significantly higher cognitive flexibility than LA readers. Teacher-administered EF intervention improved reading fluency for LA readers. These findings expand understanding of the neurocognitive basis of reading fluency and add to the growing body of evidence that EF underlies learning differences and serves as a useful target of intervention for LA students.