The Statistical Concepts Package (STAT-CONCEPT) is a coordinated collection of interactive computer programs and printed materials designed to enrich graduate instruction in educational statistics. Probability, descriptive statistics, sampling distributions, and power are four of the thirteen topics included. By doing the computational labor and providing a responsive enrivornment, the computer frees the student to explore statistical concepts in a "what happens if ...," laboratory-type, investigative atmosphere. This paper discusses the rationale, content, and student-program interaction of the STAT-CONCEPT package. Technical aspects as well as the package's usage during the past two years are also discussed. (Author)