Building minds with blocks: The impact of a play-based professional development on preschool teachers' competencies and children's learning

The study examined the impact of Professional Development (PD) on preschool teachers' content knowledge (CK), pedagogical content knowledge (PCK), and scaffolding practice. In a pre-post-follow-up design, 77 teachers were assigned to three groups (EG1: block play curriculum materials + PD, EG2: block-play curriculum materials, CG: no materials). Results showed improvements in teachers' scaffolding after the PD, but no changes in CK or PCK. The use of block-play curriculum materials and scaffolding was associated with an improvement in children's math knowledge, but not with their stability knowledge. The study highlights the need for practice-oriented PD aligned with preschool teachers' everyday practice. • Scaffolding-focused PD improved preschool teachers' instructional strategies. • Reflective practice was effectively encouraged through brief demonstrations. • PD improved children's math knowledge but not their stability theories. • Short-term PD can enhance teaching practices when aligned with daily routines.