As a highschool mechanics class teacher, I had a lot of different students come through my class. Some guys knew everything about cars, inside and out. They lived and breathed what it took to make a car function. I also had girls that knew nothing about cars and were only there because they liked the boys. One of the things that I felt was important was the maintenance of a car. I made every student do an oil comparison and tell me what the best kind of oil was for their particular car. I heard groans and complaints but I knew that their future cars would always stay well maintained.