The book is primarily aimed at students in teacher training programs. It is designed to help prepare them adequately for their future teaching in schools. Additionally, it can serve as an elementary introduction to stochastic processes for anyone else interested in the subject. The first author has taught lectures on stochastic processes at the Technical University of Munich for several years, focusing on the connection to teaching opportunities in schools. Numerous illustrations and basic examples are included to provide a sense of the surprises of probability theory. The text has been critically reviewed by students and has been supplemented and improved in many areas as a result.