Creating a classroom learning environment that is suitably designed for promotion of learners' performance in geometry, a branch of mathematics that addresses spatial sense and geometric reasoning, is a daunting task. This article focuses on how grade 8 teachers' action learning changed the learning environment for the promotion of geometry teaching. This was an exploratory study in which a sample of 13 grade 8 mathematics teachers from the rural schools of a district in the Eastern Cape Province in South Africa participated in a project aimed at creating mathematical learning environments through action learning while supporting and promoting the teaching of geometry. The study was qualitative and data was collected using questionnaires, classroom observations and semi-structured interviews with the teachers on a participatory action research conducted in two cycles. Results indicated that 92% of teachers changed their classroom environments by modifying instructional strategies, learner-interactions, and engagements, but could not change how they managed the classrooms due to some factors related to power dynamics and the education policy. It is recommended that teachers be workshopped on modifying their classroom learning environments while they undergo learning in action on the promotion of teaching and learning geometry in their school defining contexts.