  The flipped classroom has become famous as an effective educational method
that flips the purpose of classroom study and homework. In this paper, we
propose a video learning system for flipped classrooms, called Response
Collector, which enables students to record their responses to preparation
videos. Our system provides response visualization for teachers and students to
understand what they have acquired and questioned. We performed a practical
user study of our system in a flipped classroom setup. The results show that
students preferred to use the proposed method as the inputting method, rather
than naive methods. Moreover, sharing responses among students was helpful for
resolving individual students' questions, and students were satisfied with the
use of our system.
