Teacher: show an animation resource called «Exponential situations», which is useful to contextualize students in diverse situations of the exponential function, and the functional models derived from ethnographic, bacteriological and financial studies. A superficial description of each example is provided to recognize the important elements in each model. Finally, some questions are presented to motivate the student to explore situations and contexts with similar aspects. Do you know any phenomenon of exponential growth or decay? Which one? Can you imagine a situation with the characteristics?