Teaching computing in schools has become a worldwide trend. This is operationalized through diverse instructional methods, including educational games. As it is essential to systematically evaluate the quality of such games for computing education in school, the objective of this article is to present the design and evaluation of the MEEGA+KIDS model, a customization of the prominent method MEEGA+, a reliable and valid method to evaluate games. It has been tailored to the specific target audience (secondary school) through a participatory design approach by decomposing evaluation goals into measures and defining a standardized measurement instrument in the form of a self-assessment questionnaire. Results of a reliability and validity analysis of the model, based on a sample of 90 students, show evidence of its reliability (Cronbach’s alpha α=.882) and a first indication of its validity. The MEEGA+KIDS model can, thus, support game creators, instructors and researchers during the game design process and contribute to their improvement and effective adoption in practice.