According to Bakhtin (2011), each sphere of human activity elaborates its relatively stable types of utterances: the speech genres. As the spheres develop, subjects modify and re-elaborate the genres. Recent research studies, such as the one developed by Costa (2010), have proposed that the phenomenon of re-elaboration transforms speech genres. This can lead to the emergence of a new genre — creative re-elaboration — or to the modification of a preexisting genre — external innovative re-elaboration (incorporation of characteristics of other genres) or internal innovative re-elaboration (adaptation to new communicative requirements). In this work, we analyze the phenomenon of genre re-elaboration in tweets — texts of up to 280 characters published on the social network Twitter — that have educational purposes. To this end, we make a qualitative descriptive analysis of four tweets that contain topics related to the areas of Humanities, Mathematics, Languages, and Natural Sciences. These tweets were saved through screenshots. The data analysis showed that various genres are re-elaborated within the tweets, such as the entrance exam question, the advertisement, the Instagram post, the math problem, the summary, among others. The diversity of genres re-elaborated on Twitter shows the active attitudes taken by the speaking subjects in transforming genres. We also emphasize that many of these re-elaborations are enhanced by the multisemiotic resources offered by Twitter, like polls, pictures, links, hashtags, and quote tweets.