The Brown Stairs Insets are designed as an extension activity for the Brown Stairs, providing children with additional opportunities to refine their visual discrimination of size and dimension. Each inset card corresponds to a specific prism size, allowing children to match the prisms with the correct inset. This activity reinforces concepts of sequencing, gradation, and spatial relationships while promoting fine motor skills and concentration. The Brown Stairs Insets complement the standard Brown Stairs material, enhancing cognitive and mathematical development in Montessori environments.