Educators have claimed that listening to music in a second or foreign language (L2) can provide fun and motivating educational material and that singing can enhance the L2 learning process by improving listening and speaking skills, pronunciation, intonation, and vocabulary. Experiments have shown that under certain conditions, a sung presentation of linguistic material can facilitate verbal learning in the native language. To date, however, there is very little research evidence that singing can increase L2 skills. This thesis begins to methodically evaluate whether listening to songs and singing in a new language can facilitate L2 learning, compared to practising L2 material through more traditional, speech-based instructional methods. The research studies also explore the extent to which individual differences (IDs) between learners may mediate any observed benefits of using songs in L2 instruction. The first two studies examine under controlled experimental conditions whether singing can support adults’ beginning-level modern language learning compared to speech over a short time period. Results indicate that when no significant group differences exist for the ID measures, an instructional method that incorporates L2 singing can facilitate short-term learning and memory. Results also showed that IDs between learners, in particular previous language learning experience, musical abilities, mood, and motivation, can mediate the benefits of L2 learning through a singing method. The third study describes a four-week, classroom-based arts intervention exploring the effects of incorporating songs and dramatic dialogues into the L2 curriculum, both in terms of learning outcomes and the adolescents’ opinions. In addition to increases in French skills, many children reported that the dramatic and musical activities had increased their confidence to speak in French. There was also an overall preference for listening to songs and more children reported that the songs repeated in their heads after class. The thesis concludes by discussing practical implications for L2 instruction and proposes a framework to guide future research exploring how and why singing can support modern foreign language learning.