Michael Drinkwater, Joel Corney, Margaret Wegener and the team from UoQ have had some success with a 'just-in-time' approach:
I enclose our paper which was published this month describing our ‘integrated’ approach. Basically we have set up an approach to facilitate good in-class discussion based on very fast analysis of pre-reading quiz the students have to submit before every lecture. We use algorithms to extract themes from short-answer text responses. This lets us walk in to class already knowing what they are finding difficult… expressed in their own words not those of experts.