Co-teaching was originally created as a strategy in the teaching-learning process with the objective of offering inclusive, diverse participation to students. This investigation was a case study with qualitative methodology with a goal to determine the participation of general classroom teachers in the use of a co-teaching strategy-together with a differentiated education teacher-in a school with a School Integration Project in the Araucanía Region, Chile. The data were collected by semi-structured interviews with the teachers involved. The data were coded and analyzed through category creation. The results show that coordination exists between general primary school teachers and differentiated education teachers, as well as a process of critical meditation on their teaching performance by the teachers. However, the teachers pointed out that a shortage of time for planning, evaluations, and preparing teaching material was a hindrance factor, as was the heavy timetable burden on differentiated education teachers. The latter proved critical when trying to connect the two teachers in a process which should be enriching for all those involved.