Under the European Higher Education Framework the competences assessment and the differenciated assessment have become fundamental in order to increase the overall education quality and the proper development of skills in our university students. There exist multiple research works and studies regarding this issue focused on the subjects that consitute the curricula of Degrees and Masters, but very few of them face this issue on the Degree or Master Final Thesis.

In the particular case of Engineering studies in Spain, a Degree or Master Final Thesis (previously called Final Projects) were mandatory to pass successfully the universitary studies. However, only one modality was established: Technical Project, where the student had to demonstrate he was able to carry out a complete Technical Project from real or simulated data. Fortunately, with the transformation of the educational plans in 2010, two more options were given to the students: Technical Report and Research Work. However, several assessment difficulties arrised then. On the one hand, some evaluation panels went on doing the assessment as they are used to do in the former plans and then, Final Thesis that do not fulfill the Technical Project standards were heavily penalised. On the other hand, low quality Technical Reports and Research Works were given unjustified higher marks than the ones they really desearve just because they were different or the assessment panel had no enough references to compare.

In this paper, the authors first analyse the situation and then they carry out a deep study about the converging and the separating criteria between the three Final Thesis modalities. Thus, main descriptors for each modality are extracted and, finally, an assessment guide tool is proposed. This tool intends to guarantee a differentiated assessment and help to identify, in an objective manner, cases of abnormal excellence of a Degree or Master Final Thesis regardless the modality.

Although the methodology has been developed focusing on Engineering Degree and Master studies from the Spanish curricula, and the University of León has been selected as case study, obtained results can be easily extrapolated to other fields and educational plans.