She could have low thyroid. I was just diagnosed a year ago. I was sleeping about 10 hours a night, still waking up tired, and taking naps if I got the chance. I went to the doctor, was diagnosed as low thyroid (which is very common), and went on Armour thyroid. It changed my life! I had a project at school a couple of months later (I'm 44, not a student), and I was able to stay up most nights for about a month, averaging only 5 or so hours a night of sleep. I felt great! Have her check her thyroid. If she can't get to a doctor, a couple of quick easy tests are your pulse and temperature. Take your pulse the first thing in the morning, before you even move around any. If it is low, mine was only 53, then you MIGHT be low thyroid. Also, if you take your temperature, when you are resting and not overheated or anything, and it is low, mine was 97 degrees, you might be low thyroid. Check it out!