This paper aims to identify, through a field work, the conversions and the treatments in the register of semiotic representations produced by students from their interaction with digital videos. Therefore, we present a categorization of digital videos, according to Mayer’s cognitive theory of multimedia learning, seeking possible relations of semiotic representation registers that appear in the videos with those submitted by the students in writing activities. The videos deal with the content of: rule of three, linear equations, polynomial function graph, modular functions, rational function, trigonometric functions, derivative function and integral function. The research subjects were thirteen students beginning undergraduate courses in Physics, Chemistry, Education, Production Engineering, Textile Engineering, Mathematics and Production Engineering with emphasis in Agribusiness. We have noted, from the point of view of mathematical contents, different semiotic representations expressed by the students in activities related to the same digital video. The results show that students do not restrict their representations to the content alone, on what the videos show, but they connect that information with their own ideas
