Abstract:

Computational Thinking has recently been introduced as a key mathematical competence in basic education in Portugal, posing new challenges for teachers and teacher education. This study reports on a teaching experience developed within an in-service teacher training programme focused on the design, implementation and reflection on classroom tasks aimed at fostering Computational Thinking in primary school students.

The experience involved a collaborative group of four first-grade teachers who designed and implemented a task with children aged 6 to 7 across four classrooms. The study was guided by a design research approach grounded in exploratory mathematics teaching. Data were collected from teachers’ planning documents, implementation records and students’ productions. The aims were to describe the collaborative process through which teachers planned, enacted and reflected on the task, and to analyse the Computational Thinking practices evidenced by students during the activity.

The task challenged students to identify valid paths in a network under specific constraints. This activity encouraged learners to simplify relevant information, recognise regularities, test possible solutions and identify mistakes. The results show that students were highly engaged and persistent, working collaboratively to explore different paths and record their reasoning. Evidence of abstraction, pattern recognition and debugging was particularly visible in students’ responses. At the same time, difficulties emerged in adopting systematic strategies that would enable students to generate all possible solutions without repetition.

The study also highlights the value of collaborative lesson planning in teacher professional development. Anticipating students’ difficulties and discussing possible teacher actions increased participants confidence and supported more purposeful classroom interventions. The findings suggest that carefully designed exploratory tasks can promote key Computational Thinking practices from the early years of schooling, and that teacher training plays a decisive role in making this curricular innovation meaningful in classroom practice.

Keywords:

Computational thinking, in-service teacher training, primary education.