What concept must be understood before progressing to base 10 blocks?

Unitizing is the correct concept to understand before progressing to base 10 blocks because it involves recognizing and grouping quantities in a meaningful way. In early mathematical development, unitizing allows children to comprehend how numbers can represent sets of items or collections. This skill facilitates the understanding of place value, which is foundational for utilizing base 10 blocks.

Base 10 blocks are designed to visually and tangibly represent different values: single units for ones, rods for tens, and flats for hundreds. By mastering unitizing, children can effectively manipulate these blocks, making it easier to grasp operations such as addition, subtraction, and basic numerical relationships. Understanding this concept helps them transition from counting individual items to grouping them, which is essential when using base 10 blocks.