The work of mathematics teachers happens most of the time in the privacy of paper and pencil. The possible frustrations when being challenged by a big problem lead naturally to the elimination of the trace of errors. What we forget, is that by doing such a simple act of crumpling the paper and throwing it away, a phenomenon that is surely irreversible, a beautiful and interesting mathematical problem is generated: The crumpling paper model. It becomes attractive to capture the disorder and chaos that is evident in this new mathematical landscape. Valleys, shadows and roads of ideas, which appear and hide to be portrayed and returned to the beginning of the problem. This series presents 3 fields of interest: Combinatorial, Expectation Value and dynamic longitudinal systems for the analysis of retrovirals in people with HIV.