A comparison of the effects of extensive and intensive reading approaches on the vocabulary development of Korean secondary EFL learners

Although language experts have long advocated the use of Extensive Reading (ER) to enhance vocabulary acquisition, the widespread use of the more traditional Intensive Reading (IR) approach prevails in English as Foreign Language (EFL) settings. Many experimental studies have attempted to demonstrate the benefits of using ER over IR in classroom contexts; however, none have demonstrated significant differences in learning gains. This quasi-experimental study involved the measurement of partial vocabulary knowledge of specific words encountered through reading to compare the effects of ER and conventional IR instruction on EFL learners’ vocabulary knowledge development. Two intact classes of 72 Korean secondary students (36/class) received either ER or IR instructional treatments over a 12-week timespan, with pre- and post- performance differences examined by proficiency level. ANCOVA results showed that students benefited significantly more from the ER than from the IR treatment in terms of their knowledge of the meanings and uses of target words. With regard to proficiency, advanced and intermediate level learners benefited more from ER, while low level learners benefited more from IR. These findings suggest that EFL practitioners should carefully consider their learners’ proficiency level when selecting a reading approach, in order to optimize learners’ vocabulary development.