One of the hardest challenges I have faced is helping students who work full time during the day, find the motivation needed to stay on task and focus at night.
One of the best motivational tools I have found so far is to try and focus on the long term impacts of learning and understanding the course material. I always try to relate to the students that the core skills they learn in the classroom have daily relevance in their chosen career field. I find that if I help the students focus on how a subject will apply to them in the field they generally rub the sleep from their eyes and sit a little straighter in their chairs to take my lecture in.