This paper discusses two programs that have been written to be aids to introductory programming students. They both embody the belief that Computer Assisted Instruction can be a worthwhile aid to students when properly used and that one of the best uses is to present visually to the student a process that he has some control over and which he would not otherwise be able to observe. Section 2 of this paper discusses HYCOMP1, an interactive visual computer simulator. Section 3 discusses IVF, the Interactive Visual FORTRAN interpreter. They were both written in SNOBOL4 1 and run under the KRONOS Time Sharing System on a CDC 6600 using an Applied Digital Data Systems, Inc. ADDS Consul 880 terminal, which is an ASCII terminal with a CRT display and an addressable cursor.