Learning software testing is a neglected subject in computer science courses. Over the years, methods and tools have appeared to provide educational support for this learning. Mutation testing is a technique used to evaluate the effectiveness of test suites. Recently, a variant called extreme mutation testing that reduces computational and time costs has emerged. Descartes, an extreme mutation engine was developed. With the support of a plugin extension called Reneri, Descartes can generate a report providing information to the developer on potential reasons why mutants remain undetected. In this thesis, an extension of Visual Studio Code has been developed in order to incorporate the information generated by Descartes and Reneri. The purpose of the experiment is to assess whether the inclusion of this data can help master’s students improve their test assertions. The results showed that this information integrated into an editor was well received by the students and that it guided them towards a refinement of their suite of tests.