This paper reports on a study that was conducted in a low socio-economic primary school in Santiago, Chile, where a sample of ten selected students (five monolingual Spanish Chilean students and five non-native Spanish speakers from Haiti) each wore a mini video camera mounted on eyeglasses in their mathematics lessons. Using Google images, frames from the recordings where the classroom teacher appeared in the students’ visual field were captured and analysed automatically and objectively (without the observer’s bias). This paper examines the differences of monolingual and multilingual learners’ visual attentions in their mathematics lesson as the mathematics teacher was conveying the instructional information in Spanish. The results show that multilingual Haitian students paid significantly more visual attention and were visually two and a half times more engaged throughout the lesson than their native Chilean counterparts. This could be assumed due to their lack of comprehension in Spanish, Haitian students consequently paid a great more visual attention to compensate for their understanding looking at different modes of communication such as gestures and other modes of meaning making that was conveyed nonverbally by the teacher. The results of this study can have further practical pedagogical implications, particularly in contexts where the medium of instruction is not the same as the learners’ mother tongue.