The present article reports partial results of an investigation which aimed to examine the strategies used for solving addition and subtraction operations. The research was performed with seven adolescents aged between 12:04 and 15:11 years, diagnosed with deep deafness and in the pre-linguistic phase, in situations of peer interaction. From the results, some recommendations were prepared aiming to improve the mathematical performance of this population. The interpretation of error types and an understanding of the strategies used by the students constitute relevant aspects for the improvement of teacher's professional development. Some of the detected error types have specific characteristics different from those previously described in the literature.
Deaf adolescents; Mathematics education; Solving strategies; Addition and subtraction
