The purpose of this study is to examine the effects of web-based and process oriented writing instruction on students’ writing skills in the elementary English class. Using a webtoon maker and SNS(Social Networking Service), called Classting, three groups of fifth graders(a total of 63 students) participated in different modes of writing activities for 18 weeks. One experimental group used Classting and the online cartoon maker tool while another experimental group engaged in a pencil and paper-based cartoon activity. The control group participated in a regular English class focused on textbook work. The results showed that the cartoon activities had a positive impact on the writing skills of students in the experimental groups and students had more interest and self-confidence in writing than the control group. It was found from the questionnaire, interviews, and teacher's field notes that students in the first experimental group were satisfied with the collaborative writing activity, exchanging feedback with their peers and teacher through SNS and creating their own cartoon while writing. The results also revealed that students’ communicative competence had improved through sharing knowledge, mediating conflicts of opinion, and making cartoons using the Internet. Further study is recommended for the improvement of learner's speaking, reading, and writing abilities through the incorporation of new SNS applications and animations into the English classroom.