Graphical programming languages such as Simulink, Hypersignal and others have been coming into use recently for rapid prototyping of DSP algorithms. Using such languages amounts to dragging functional blocks from libraries and connecting them to form a block diagram, which is also a program. Beyond their value to application development, these programming languages are also very useful as classroom teaching AIDS. In this paper we present a number of useful demonstrations in Simulink. Each of them demonstrates interesting aspects of DSP, and are useful for classroom demonstrations and as a basis for further experimentation by the students. Using them can enhance the students grasp of complicated subjects in DSP, and increase their interest in the subject matter. The major advantages of using Simulink for this purpose is that constructing them requires a relatively small investment of time on the part of the instructor, and that they can easily be extended and experimented on by the students.