Student performance in a flipped classroom with an animation-based content knowledge development system for the bottom third of the incoming first year college students was compared to that in a traditional lecture-based teaching method. 52% of these students withdrew from the traditionally taught General Chemistry course, compared to 22% in a similar course taught in a flipped classroom teaching method. Of the students who persisted in the course and obtained a grade, there was an increase in A's and B's as well as an increase in D's and F's for students taught in a flipped classroom teaching method when compared to those in the traditional setting. When the course that was initially taught in a flipped classroom method reverted to a traditional teaching method, students in that course generally performed worse than students who were in a traditionally taught course all throughout.