Social communication is now gradually shifting from unilateral (verbal or written) to multimodal (a combination of language and non-verbal media). Therefore, guiding students to practice to develop multilateral text creation skills is an inevitable requirement for high schools, especially when teaching Literature subjects. Because this is one of the important skills required by twenty-first-century citizens. Therefore, we conducted the study “Developing multimodal text creation skills for high school students through lesson: Writing a letters to exchange aboutt an outstanding social issue”. Specifically, we define the theoretical basis for the characteristics of the type of post. After that, experimental teaching was organized for students of classes 12A1 and 12A6 of My Xuyen High School, Can Tho city, Vietnam. From the learning results of the two experimental classes and the comparison with the academic performance of the same classes, it has been shown that the teaching measures we proposed have brought positive results and can be widely applied in high schools.