This is interesting, and a lot of money to be made for sure. At my University, an entrepreneur professor of mine was running a $20,000 course, and they were doing very well on Coursera.
If the admission of a student to the course is $9,000, I would try to find out what the average cost to the School is for each head (faculty, and other expenditures), and how many leads it takes for them to convert. Back to my professor's example, a heavy cost for them was running paid ads, which is effectively an expenditure that you would be knocking out, or replacing for them.
Finding out that # would give you more ammo in determining a reasonable commission number. Realistically, for the school niche, 5 - 10% would be extremely reasonable, however without knowing those numbers, and how much it would cost you to generate each lead, anything would be arbitrary
For cost per lead, you can let Google Adwords help. Look at what the market rate is (CPC) * 100 clicks. Then I would divide it by 5 - 10% (of how many will actually call).
This can help you get an idea of fair market value. If CPC for these type of courses is $8, I would charge about $100 a lead (8 * 100 / 8)
I love the commission model because of how lucrative it can be, but it's burned me plenty of times. From relying on the shoddy salesmanship of contractors, them not answering all of the phone calls ... to them not accurately reporting all sales (intentionally, or not), it can be a real headache. You're also operating in an entirely different vertical, so it might have completely different results than operating on a revenue-share model in a blue-collar niche. If you have rapport and trust with the client, that goes a looong way.
So, do you use organic, or paid media to generate leads?
