In 2013, evaluators of the Brazilian Textbook Program reported that many digital tools to be added to Science textbooks were rejected for not meeting the criteria established at the program s announcement. With the aid of real-world examples, three of these criteria are analyzed and a list of recommendations for the design of digital learning tools is presented, including recommendations such as: to promote meaningful learning, experimentation and the active participation of students; to present didactic guidelines for teachers; to create an intuitive interface, avoiding the use of many instructions; to provide feedback and to take into consideration the main steps of scientific inquiry in the case of learning objects for Sciences. Based on these recommendations, a desktop/web and mobile application for students from 6th to 8th grade was designed. Through the use of the application, students would learn how to mitigate risks related to the Aedes aegypti mosquito, by manipulating environmental factors that affect the development of its larvae. Interventions targeting the larval stage are the most effective kind of control of the mosquito. Relevance of the subject is attested by more than 1.5 million cases of Dengue fever reported in Brazil in 2015 and the recent Zika fever outbreak.