This article deals with an introduction of probability at school through sensory modalities. This approach is based on sampling fluctuation with empirical observations of frequencies. Initially, we analyze how students from high school work on such a task by using dice, pencil, and paper. We then identify the use of schemas and data visualization by students. Considering schemas as a primitive form of algorithmic approaches, we observe interaction with mathematics. In class, students know how to use notion of frequency, but linking frequencies with probability appears to be a difficult issue. This absence of a statistical link leads us to identify entry points for probability teaching. We then decide to analyze primary school students when they have to explore a random experiment by using statistics.