In second language (L2) teaching, instructors suddenly find themselves in an unprecedented situation where they need to quickly learn to teach with digital resources (Oskoz & Smith, 2020), regardless of their prior experiences with technology. Though COVID-19 has accelerated this process, it had already been well documented that language teachers were struggling with overcoming the anxiety associated with teaching with technology (e.g., Kessler, 2010; Son, 2018). Given the immediate need for L2 teachers to develop computer assisted language learning (CALL) resources for their students to use, they are likely to remain anxious or confused about how to achieve this without an approach to guide them. Therefore, an approach to CALL customization is needed in order to: (1) enable L2 teachers to conceptualize and develop their own technology-enhanced materials, based on their time, resources, and comfort with technology; and (2) afford these teachers’ students a variety of ways to use the target language in interactions with and through technology, in digitally-facilitated exchanges. To this end, the three interconnected manuscripts in this dissertation aim to: (1) propose an approach that recognizes teachers as customizers of CALL resources directed at stimulating L2 use, based on their expertise and comfort with technology (manuscript A); (2) investigate the effect that materials made according to this approach have on the development of L2 pronunciation (manuscript B); and (3) assess the implementation of the proposed approach from a pre-service teacher’s perspective (manuscript C). The data from manuscript B support that the customization of CALL resources can contribute to L2 learning, while the data from manuscript C show that teachers can use the proposed approach to become aware of their abilities in CALL, in addition to customizing a wide range of CALL resources.