I would consider what jobs they are doing; if it is academic-related jobs such as classifying books, etc., or medically related things, I would put it under an academic classification such as literature, etc. If it is other things, perhaps it could be non-academic credit in something like work skills, etc. Some of it would depend on their age and goals, but I think my children learned as much in these "work-related" areas as through books, even if they are not paid. The public school has students go into work areas as part of their education, too. In Missouri, where I live, the records divide into academic and non-academic hours, so it would depend here on what type of work they are doing. All in all, the answer I would say is "YES" it can be included as class time.
Deanna