The Hook-ups project introduces a new set of tools and activities intended to support children in creating physical computer input devices for computer programs they write. This project introduces a new approach to learning through design by providing opportunities for children to engage in both the physical and computational design concurrently. This demonstration proposal describes three types of Hookups (basic, repurposed, and fabricated) and introduces a set of puzzle piece-based building blocks called Scratch Patches that youth can connect to construct physical input devices. In this demonstration session, participants will have the opportunity to interact with existing Hook-ups interfaces, including several designed by youth, and construct their own Hook-ups.