Then discuss that subject in class. You will find that you can spend less time teaching formulas and definitions because the students have had time to work with them, visualize their consequences, and apply them to real data. This leaves more time for examples, discussion, remedial background work, and extra time on the really hard concepts. You will find that it is not necessary to change your lectures substantially. Rather, you can change the emphasis away from the nitty-gritty of formulas and definitions and towards philosophy, the big picture, and examples.
Most textbooks are hard for students to read without some introduction.
Textbook readings seem to be most useful after students have seen the topics in ActivStats and in class. It is a good idea to assign homework exercises from ActivStats and texts only at the time of the classroom discussion to reduce the number of students who try to work the exercises first and then look back to see what they need to know to work the problem. Because the questions are in the middle of a narrated activity, it is easier for students to work through the activity than to search for the questions directly. Another method is to administer a brief quiz at the start of a class meeting. Working with the CD is a new skill for students.