Hi Skyman68,
I am assuming that your post is a wind up.
It may not be the CFIs job to check the visa, as that should be the admin side of the school. If you are operating from a small school in the middle of nowhere, then you are probably a US citizen anyways. Most foreign nationals will be teaching at slightly larger schools that can offer the correct visas.
Legally you can teach who you want, but if you are on a J-1 visa you will only be allowed to work where you want once they have transferred your visa to another school if you move from the original one that issued it, even then the original school still holds your visa.
Any flight training that it not just hour building toward another foreign license will require a minimum of the student to hold an M-1 visa.
If you are just hour building for say the JAA license I believe that UK citizens can just enter the country on the 90 day visa waiver.
If you set yourself up to accept any student and you here that they are not legal in the US it would be your responsibility to tell INS (They are now called something else USCIS, I think?)
If INS then did a check on your students and found that you had just called a load of people in from Europe and told them not to get a visa or the vast majority did not have a visa, then if you were not a US citizen you would more than likely be removed from the country and be black listed.
Things have changed here, I was here before 9/11 and the number of people that were working in aviation under the incorrect visa and work cards was amazing.
Since 9/11 it has become a whole new ball game.
I am not sure what Jim wants to do whether to stay in the US or go back to the UK. Either way being black listed by US INS is not a good way to go.
If you follow Skyman68's advise you could be looking at being black listed from the US for 10 years.
Airlines still ask whether you have unrestricted entry into the US.
Do not do something that can affect your career before it has even started.
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