I teach Intro to Computers and find that my typical class features the 18 year olds who do not know life without a computer and can teach the class to the 50 year olds who have never used a computer before. During the first week of class, I can easily spot who is having trouble using a mouse and who is a wiz. I make all of my projects group work and assign tasks to each group member. We rotate with each assignment. This gives opportunity for all to help eachother learn. I find this strategy helps the learning process by giving the "computer wiz" an opportunity to practice helping others - which they will be called upon to do in the real world" as well as a great environment for others to receive assistance from multiple people. I find it difficult in a large class to give my whole time to 2 or 3 students. This seems to work well for me.