This module introduces the student to a formal study of probability. The lessons progress from elementary notions of least likely to more complex considerations of the probability of occurrence of one or more possible outcomes. Probability is introduced in an empirical sense through experimentation and investigation. In the later experiments, the students are shown how mathematical probability differs from empirical probability. The last three experiments of the module demand some fairly mature thinking on the part of the students. The teacher may prefer to use a classroom setting if these three experiments are used. (Author/MK)