Coffee Maker updage

Over the past dozen years I have taught, and continue to teach, OO design to professional software developers. My courses are divided into morning lectures and afternoon exercises. For the exercises I will divide the class up into teams and have them solve a design
problem using UML. The next morning we choose one or two teams to present their solutions on a white board, and we critique their designs.
I have taught these courses hundreds of times and have noticed that there is a group of
design mistakes that are commonly made by the students. This chapter presents a few of
the most common errors, shows why they are errors, and addresses how they can be corrected. Then it goes on to solve the problem in a way that I think resolves all the design forces nicely.