Background: The perception that educating learners using their mother tongue contributes positively to educational and learning outcomes is well documented. Aim: This study explores the purported benefits of employing the mother tongue in teaching Foundation Phase (FP) learners. Specifically, the study focuses on an examination of the experiences of teachers of isiXhosa (one of the indigenous languages in South Africa) and explains the effects of employing isiXhosa in teaching at the FP (Grades 1-3). Setting: The study was conducted in three rural schools in the Eastern Cape. Methods: The study utilised a qualitative approach and case study design was followed. The sample comprised nine FP teachers (one male and eight females) who were selected purposively from three public schools. Three FP teachers were selected from each school and the one-on-one interview was used to collect data. The collected data were analysed thematically. Results: This study revealed that a majority of FP teachers had not received training to teach subjects using isiXhosa as a medium of instruction. This study also revealed that teachers encountered numerous difficulties in teaching mathematics and life skills using isiXhosa as a medium because of lack of vocabulary to match mathematics and life skills concepts. Conclusion: The authors suggest that teacher training institutions should provide adequate and relevant professional training to FP teachers so that they could teach in isiXhosa optimally. The authors also suggest that all textbooks, readers, educational media, study guides and related literature be made available in isiXhosa.