Surley there must be some good responses? (maybe even if it is just a smile or a handshake.) Your employer would give you the boot if they thought you had no content to offer and I bet collegues get the same kind of abuse. I instructed wood carving for two years and I got good replies because I had mature students who elected to be there because of an enjoyment factor, but if you are teaching a bunch of young punks who are only putting in time to get a diploma, then you will get immature replies. Don't read those anymore. I bet there are a lot of people that relate to you and it never occured to them to give you the praise you deserve. Do what you love and teach what excites you and to hell with the opinion of the masses. Even helping one person is a blessing. I for one know how difficult it is to teach to a room of blank faces and I give you my support and respect.