Super-absorbent polymers (SAPs) absorb and retain water up to several hundred times their mass and increase in volume up to 600%. Unlike this prop, students’ brains do not grow/learn by passive absorption of received knowledge from the outside. Learning is an interactive, psychologically active, inside-out and outside-in process that involves both assimilation and accommodation of new experiences and ideas into preexisting conceptual frameworks. In professional development contexts that focus on brain science, the Growing Brain can serve as a visual participatory analogy to initiate a discussion about brain “growth” as related to learning in educationally enriched environments.