Does labor law apply to graduate students? As a former student employee, I was fairly ignorant of labor laws in general. But now as I am applying to graduate programs, given the increased demands and duties of graduate students: teaching, research, etc. I wonder if US labor laws still apply to student labor in general. 

Given anecdotal stories of overstressed graduate students working well beyond a ‘planned’ 40 work week on a stipend that when calculated on a per hour basis may equate to less than minimum wage; and the types of work that students do: laboratory research, fieldwork, custodial, food service, etc. Surely there are protections in place to prevent abuse and overworking students of all types.
Graduate students fall into a gray area with respect to American labor law, because they are a bit of a hybrid between students and employees. At least for the first year or two, they are usually mostly taking classes, and doing some research, but the balance shifts more toward research in later years. 

As for the number of hours worked:


  Research ideas don't wait until you punch in in the morning.


The expected workload completely depends on the culture of the lab. I knew of groups in my old department where there really were no "expected schedules," and other groups where the expectation was about 80 hours per week! 

That said, graduate students in my department worked a wide variety of different schedules. Some were night owls, who showed up around 10 or 11 at night, and stayed until 8 in the morning. Others were punctually showing up around 9 am and sticking around to 5 or 5:30 in the evening—and everything else imaginable.

Personally, there were days when I worked from 8:00 to 6:00 or so; other days around deadlines I might work until midnight; still other days I'd take a half-day or so.