Pedagogical agents (PAs) are lifelike characters in virtual environments that help facilitate learning through social interactions and the virtual real relationships with the learners. This study explored whether and how PA gesture design impacts learning and agent social acceptance when used with elementary students learning foreign language grammar. Unlike prior research, this study examined the effects of PA gestures in three conditions: full gesture condition (deictic, iconic, metaphoric, and beat gestures), deictic gesture condition, and no gesture condition. Transfer of knowledge, retention, and agent social acceptance data were collected from 160 South Korean 5th and 6th graders learning about using "-er/more" for comparatives in English. Retention and transfer test data revealed no significant differences in learning outcomes across conditions. Regarding social acceptance, PA in the full gesture condition was perceived as significantly more human-like and engaging than PA in the no gesture condition. However, multiple regression revealed that social acceptance factors "human-like" and "engaging" were also negative predictors of learning outcome scores. This finding suggests full gesture PAs may have the ability to increase social perception by learners, but the novelty of PAs with full gestures may also have an initial negative effect on learning outcomes.