Any course in numerical mathematics must set out to help the student to interpret the numerical results obtained from calculations. The characteristics of round‐off error, stability and ill‐conditioning of the results must be considered before the results are accepted. Although the effects of the above can be shown in theory, it is more difficult to recognize them in practice, and it is considered that graphical presentation of these effects can assist the student greatly.Manual graphing of results is laborious and time‐consuming, and in many institutions, students now make use of computer systems to demonstrate the characteristics of various numerical techniques. This in itself can be a significant undertaking when the student is required to learn a procedure‐oriented computer language, and be required to program his numerical methods in that language. Since the process of programming and testing a method may interfere with the student's comprehension of the underlying principles of the numerical techniques, a better approach demonstrating the numerical methods is sought.NATEP is a numerical analysis teaching package that makes use of an established author language (STAF) to facilitate student‐machine communication. A wide variety of numerical techniques have been implemented and the student can readily use these with his own functions and parameters. A graphical output is obtained cheaply and conveniently on a graph plotter. The system has proved to be highly effective and useful in the teaching environment.