This paper presents a controlled pretest–training–posttest study on using a small membraphone instrument called kazoo for L2 pronunciation practice and reducing foreign accentedness. Learners were recorded for free speech before and after a six-week pronunciation and oral skills course including L2 prosody training with personal kazoos. A control group did not receive any kazoo training but did similar tasks in regular speech. Samples of all learners’ free speech before and after the course were rated for foreign accentedness by L1 speakers. In addition, learners taking part in the kazoo group were interviewed in focus groups to ascertain their views on kazoo training. The results imply that the kazoo has potential as a pronunciation teaching and learning tool. Even if a group-specific analysis did not yield clear results, developing on an individual level was more common in the kazoo group. Moreover, many of the learners found positive aspects about kazooing. However, problems occurred as well; these are also reported on in this paper to hopefully help others who wish to conduct further teaching experiments and develop specialised tasks and materials for kazoo pronunciation practice.