Blocks-Based Programming

A programming paradigm designed to introduce coding concepts to beginners — particularly children — by representing code as visual, interlocking blocks that are dragged and dropped to construct programs, rather than requiring typed syntax. Popular environments include Scratch, Blockly, and Snap. While blocks-based programming has dramatically lowered the barrier to learning computational thinking, most implementations rely entirely on visual drag-and-drop interaction, making them inaccessible to children who are blind or have low vision and use screen readers. Accessible alternatives have been developed using touchscreen interactions with screen reader support, keyboard navigation, or tangible blocks.