Well to be honest i try to have my lesson plans done ahead of time and what i do over the weekend i go over my material for the week and make any adjustments . If the previous term ididnt like the way things worked out , i make a not to my self and make the adjustments... For me it's always a calabration game, if something did not work for one class it might work for another. I probably prepare for about 3 hours or so and if i feel i need to adjust as i teach i do and improvise. I like to see how the class goes and i go with it. I am sure that we all plan and think our class will go one way but at the end it has a way to take off and go on it's own. Thank you for you comment and reply .