Remix and Robo are two sampler/sequencer controllers that allow children to engage in (1) storytelling, and (2) competitive endeavors with a modular robotic toy. We base this work on Topobo, a constructive assembly system with kinetic memory (the ability to record and play back physical motion). Remix is a tangible interface used to sample, organize, and manipulate several kinetic records. Robo is a modified game controller used to capture robotic motions, adjust global motion parameters, and execute kinetic recordings in real time. Remix and Robo facilitate new kinds of applications that build on children�s varying interests and social motivations. Whereas children typically play with building toys because of the joy of model-making or solving engineering problems, Remix and Robo allow users to cast their creations in performances and competitions. By introducing an expanded social scope, our work motivates learners to focus and reflect upon their understanding of dynamic physics concepts with Topobo.