We present a Sketch-Based Interface that allows non-expert users to create an animation from just pencil and paper. The interface works as a fast mockup tool for creating animations - turning the user's freehand 2D sketches into 3D animations. To facilitate animation construction in offline or computer-scarce scenarios, special emphasis is placed on paper-based instead of tablet-based sketches. The interface makes use of stroke shape, proximity, and orientation to give the user's drawings an animated interpretation. These Sketches use a 2D vocabulary of symbols, representing actors, actions and their relations. Custom symbols are defined by the user, and then associated with the relevant 3D assets within a database. The final composition of the sketches is passed into the system, employing image processing techniques for symbol recognition, and finally converting the user's intentions into a 3D animation.