The practice of statistics is the focus of the world in which professional statisticians live. To understand meaningfully what this practice is about, students need to engage in it themselves. Acknowledging the limitations of a genuine classroom setting, this study attempted to expose four classes of year 5 students (n?=?91) to an authentic experience of the practice of statistics. Setting an overall context of people's habits that are considered environmentally friendly, the students sampled their class and set criteria for being environmentally friendly based on questions from the Australian Bureau of Statistics "CensusAtSchool" site. They then analysed the data and made decisions, acknowledging their degree of certainty, about three populations based on their criteria: their class, year 5 students in their school and year 5 students in Australia. The next step was to collect a random sample the size of their class from an Australian Bureau of Statistics "population", analyse it and again make a decision about Australian year 5 students. At the end, they suggested what further research they might do. The analysis of students' responses gives insight into primary students' capacity to appreciate and understand decision-making, and to participate in the practice of statistics, a topic that has received very little attention in the literature. Based on the total possible score of 23 from student workbook entries, 80% of students achieved at least a score of 11.