In order to study the effects of in-class and out-of-class activities of college English based on the mixed teaching model on the fostering of students' English learning and application ability, the attitudes of 215 freshmen of Agricultural College, Yanbian University towards in-class and out-of-class activities and their participation and completion of tasks were investigated by a questionnaire. The results show that a series of in-class and out-of-class activities could help improve the students’ language competence as well as non-language competence such as learning strategies, emotional attitudes, and cultural awareness. The implementation and effect of school online courses were inferior to classroom teaching, but they provide reference and experience for future mixed teaching.