Dual internships?

[studebaker07]

I am just about to start the spring semester and am entertaining the idea of doing two internships. I have already started one but I just got an offer from another firm for another internship. The one I have accepted is off-site which means I can pretty much perform the duties of the internship from wherever.

The other position would require me to work at least 10 hours a week at the office. This is on top of 5 classes. I am thinking it might be a little too much but I wanted to solicit stories and past experiences from others who may have also undertaken simultaneous internships? Unfortunately, splitting is not an option here.