In order to reinforce EFL and college students' critical thinking skill in their English writing, an after-class activity of reflective essay writing on English news videos may be a method to facilitate improved writing performance. In addition, since small group learning is an effective way to enhance students' critical thinking skill, teachers and students can use Edmodo, a private social communication platform, to connect with each other and conduct collaborative learning. The purposes of this study are first, to examine whether college-level EFL college students will show improvement in their writing (that is, the writing ability and critical thinking shown in the contents) after they watch English news videos; second, to investigate students' perceptions about reflective writing on English news videos; and third, to find out their perceptions on the use of Edmodo for peer discussions. The participants in this study were 16 EFL English-major junior students in a private university in the northern Taiwan. Both quantitative and qualitative data were collected and analyzed through descriptive statistics, non-parametric test analysis, Kaplan-Meier method, document analysis, and content analysis. The scores revealed that students made significant progress in English writing and critical thinking between the essays. The majority of the students showed positive attitude toward this activity and commented that Edmodo was easy for them to discuss and upload assignments. The study is helpful for language teachers who are interested in reinforcing critical thinking in English writing and exploring the use of Edmodo in the EFL/ESL college-level composition courses.