By employing an action research framework, this study was designed to explore the effectiveness of a set of speaking activities centered on a children's cartoon to improve oral performance in the EFL classroom. The participants were fourth graders of a public school in Colombia, who had low oral performance in spoken English language. The findings suggest that the proposed speaking activities were comprehensible for the students, and appropriate to the students' proficiency level. Although to maximize learners' opportunities to speak in the classroom, teachers should design activities that provide chances to talk in English. Thus students will be engaged to participate in the classroom. Also, most of the students were comfortable speaking during the activities since they were familiar with watching cartoons, thus being at ease with certain topics can help students exchange ideas in class. The most important recommendation is to avoid translating instruction into students' mother tongue for the purpose to familiarize students with the target language.