I have had some dissappointing classes too. I enrolled in a 'tole' painting class for beginners. Their were 2 other students and I found out that they were friends and came to every class. The teacher complained about her life for 3 hours and it was not a beginning class.
Next next was a machine quilting class that was a total waste of money. No help or advise at all to ANY of the students.
I guess it happens to a lot of us.