Using computers in the educational process contributes to improving not only students’ performance, but also to the enhancement of their motivation. In this research main motivation theories were analyzed. Based on them, a tool to assess the motivation of students who use computers in education, especially students using a learning management system (LMS) was developed. In this first part of the article, the design of such an instrument is described. The validation of this tool by statistical analysis of data, obtained from its implementation on a pilot sample will be presented in the 2nd part of the article, published in a subsequent issue of the journal.