The traditional interfaces used in most graphical software have many shortcomings when applied to drawing programs in the context of geometry instruction. Among them are: High complexity, availability of shortcuts to solve problems that the student is supposed to construct by geometry; and none resemblance to real drawing instruments, preventing the student from learning how to properly handle them. A new interface for an educational geometry drawing software called {\ttRISKO} was designed to mitigate these problems and is presented in this paper. Following a pure Direct Manipulation paradigm and using a concrete, real-world metaphor style, this new interface features drawing tools (drafting triangles, compass, pencil), which behave almost like their real counterparts. Due to its characteristics, the proposed interface is intended to be very intuitive so that it does not require any operating instructions to the user and has no error messages. Also, it is able to support all compass-and-ruler geometric constructions, while training the apprentice in the proper methods for handling real drawing instruments.

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