This study documents to what extent writing on a blog in a networked learning environment could influence the affective variables of elementary-school students' writing. The framework is grounded more specifically in theory of self-determination (Deci & Ryan, 1985), relationship to writing (Chartrand & Prince, 2009) and the transactional theory of Rosenblatt (1991). The research team used both pre and post-tests to measure affective variables and the analysis was conducted on the basis of inferential and correlational statistics using SPSS 17®. Qualitative analysis is also used to identify writing intents and topics of blog posts. Results indicate an increase in motivation to write in pupils who used the blog, whereas the number of comments made per post did not seem to have any definitive impact on this subject.