I would count it toward health class credits. If the hours spent on the classes combined exceeds what you are counting as one credit, you might be able to add something to it (if needed) to grant two credits, or one credit per semester, depending on how much there is to each course.
If there is enough hands-on experience as part of the ATV course, it might count towards a PE credit, but I’m guessing it is mainly in-class safety.
