Yes - each state is different but CA is ridiculously easy. Ride around some cones, round in a circle a couple of times without putting your feet down. Job done. You have to do a written test beforehand.
There are no course / training requirements, you can just turn up and do it.
I met a guy (on a RE Himalayan) riding with a TRF group last summer. He said it was cheaper and easier to fly home to the states, do it in one day over there, and then get the license switched to a UK one when he got back.
Long shot but anyone here passed their motorcycle licence course in the States?