3L: The Southeast Asian Journal of English Language Studies – Vol 25(4): 51 – 67 http://doi.org/10.17576/3L-2019-2504-04 51 Incidental and Intentional Learning of Vocabulary among Young ESL Learners PAVANI MALAA MEGANATHAN Department of English, Faculty of Modern Languages and Communication, University Putra Malaysia YAP NGEE THAI Department of English, Faculty of Modern Languages and Communication, University Putra Malaysia ntyap@upm.edu.my SHAMALA PARAMASIVAM Department of English, Faculty of Modern Languages and Communication, University Putra Malaysia ILYANA JALALUDDIN Department of English, Faculty of Modern Languages and Communication, University Putra Malaysia ABSTRACT Developing a rich vocabulary repertoire in English is an essential achievement for young learners acquiring English as a second language (ESL) as having a strong word knowledge base supports the development of the four language skills in the second language. Most studies on vocabulary learning, however, have been conducted with adult learners at the college levels. The primary purpose of this study is to investigate the effectiveness of different instructional techniques (incidental learning and intentional learning) on vocabulary acquisition among young ESL learners. The participants were 99 students between 10-11 years old in a Malaysian Tamil primary school. Stratified sampling was applied, and the subjects were divided into 3 groups; a control group and two experimental groups: extensive reading (ER) and extensive reading plus vocabulary enhancement (ER+). The ER group received treatment involving extensive reading of storybooks while, the ER+ group received treatments involving extensive reading of storybooks and vocabulary enhancement activities. The treatments were conducted as after-class activities. The control group did not attend the after-class activity but continued with regular class activities. The vocabulary levels test (VLT) was administered to all groups before and after the treatment to measure the significant difference between the three groups. The results show a significant gain for both the experimental groups with the ER+ group having higher means in both the post- test and delayed post-test scores. However, there was no gain recorded for the control group. The study provides evidence that extensive reading can enhance vocabulary learning but the blending with vocabulary enhancement activities was more effective. Keywords: Incidental learning; intentional learning; extensive reading; vocabulary learning; graded readers INTRODUCTION With many different languages in use worldwide, knowing a second language (L2) that has socioeconomic value can give a person an edge in a multilingual world. Nevertheless, learning a L2 may not be a simple task, particularly for young learners in Malaysia who may be required to acquire multiple languages at the same time. All primary school students in Malaysia are required to learn both Malay and English in the primary school, and if they are attending Tamil or Chinese primary schools, they will be learning either Tamil or Chinese as well. Coady and Huckin (1997) has argued that developing vocabulary skills among ESL learners is fundamental to language learning and language use. Laufer and Hulstijn (2001) also noted that generally, L2 scholars and teachers know acquiring a L2 includes the learning of a sufficiently wide range of vocabulary. In a more recent study, Bei (2011) concluded that in