If you are thinking about taking a dive class, this is most likely how you will be trained with the other students. You will be on your knees at the bottom of a lake, or quarry or ocean. You will demonstrate your skills on your knees....generally overweighted so you don't float to the surface. This is bad! What happens when you are diving in deeper water and your mask floods and you need to clear it? Will you swim to the bottom and get on your knees? You want to learn to do your skills in a swimming position....not on your knees. Before you sign up for a class....ask....how many people in my class and will I be doing my skills on my knees in my first couple of open water dives. If the answer is yes......you might want to consider looking elsewhere.