The study presented in this is paper reports on the investigation of students´ engagement in an educational blog established as a project-based learning environment. Twenty-one secondary education students (aged 15 years), coming from two separate K-9 classes, were involved in this learning activity and the research reported. Using the Community of Inquiry (CoI) framework, the analysis of the content posted shed light into the multiple ways of students´ engagement into the blog learning space, namely their social and cognitive presence that supported the development of a CoI. The results suggested that the students in the sample achieved higher cognitive levels through enhancing their communication and collaboration skills, and their analytical and critical thinking as well.