The students typically respond at the end of the term regarding the class content and delivery method. I am able to use this to make quick/minor modifications, but the major modifications will take a term or two. However, I can also assess progress based on how well the class performs as a whole when new delivery methods are used. I recently released a mid-term summary outline for one of my classes because of the voluminous amount of material in the first half of the term. I plan to see how well the class performs on the final exam now that this has been put into place. Some assessments are more formal than others, but there are many ways to approach student assessment and content delivery.