This paper is to study adequacy of developing tutorial series for primary school students regarding MOS certification and to analyze a validity. In order to analyze a level of difficulty, current primary teaching materials being used after class, in comparison with ICT discretionary hour materials being used through primary discretionary class, were evaluated. It was done by primary teachers with in- depth understanding of a level of difficulty and after class instructors using Likert scale through quantitative analysis. As a result, level of PowerPoint has a satisfactory fit (76%), however, the degree of difficulty of Word and Excel is quite high. On its subject matter, there is quite a dispute with present curriculum. Therefore, in order to introduce MS-Word or Excel, it is necessary to adjust a level of difficulty or related subjects according to the level of students.