What an interesting topic!!! I have worked at Big Mountain for ten years and tips are always a bonus. I keep my tips in a special fund and use it for stuff that I want for skiing.
When I teach a group lesson, I am really happy to get a tip and most of them are from $5 to $20. I often teach people who have no idea about tipping insturctors--some of them send me cards later with tips in them!!!
With private lessons (3 hours) I almost always get a tip (from $20 to $50). when I have folks who take lots of lessons, I always tell them not to worry about the tip---I do get a bonus with requests--when the person specifically requests you. Many of them tip me at the end of the year.
With my groups that ski with me for eight weeks I have gotton tips from $50 to $100 from the women---I prefer not to know who gave what!! A tip is a generous gift and I appreciate it.
We are only paid for the hours we teach. So, even if we meet at 10 or 15 minutes before the lesson--and if we go 15 minutes over the lesson, that is all time that I am not paid for. There are days when I go to work and get my "show up" pay (which is State mandated) of $7!!!
However, having said all of this, I love teaching---I love skiing. I do need the money that I make, but I do not expect tips from people. I always give the same good service to everyone---since I am happy doing work I love, it is easy to do a good job. Lots of us, like me, spend hours in training sessions both at our hill and at PSIA events that we have to travel to do. I frequently spend $400- $500 at these events (thank you those who give me tips!!).
All of them help me to be a better instructor and I enjoy them. I know how hard it is to afford skiing. I have had some clients show up with homemade cookies or pies after a lesson--wonderbar!!! I have gotton lots of nice notes and pins and christmas ornaments!! All of which warm my soul. So, remember, if you can't afford to tip a nice note or some cookies are a great gift too.
For school groups there is hardly any expectation of a tip. However, they are mostly taught by the young instructors who need a tip. Ditto for children's group lessons. If you are the teacher, there is no need for you to top for the class. I think if the instructor got $10 he/she would be delighted. Most classes send back cute little notes to the instructors which are really fun to get and read.
When I have a private client, I try to use some video and I usually send them a video of their skiing---so, I appreciate a tip since there is extra work. But, I have clients who take me to lunch, knit me hats and invite me over for dinner and wine. A tip is a gift and if you feel that cash in inappropriate, then consider a warm thanks after the lesson or a baggie of M and M's!!!