The students should have an idea of what to focus on based on the lesson plan. I would use 90 minutes for the exam, and then plan to cover the chapters with the remainder of the time. I would focus on major concepts and break the chapters up into 2-3 activities that reinforce the content. You aren't responsible for teaching every tiny thing from the chapter. I always ask myself, "is this something that they will remember or will be important to them in 10 years?"
