Hi Lou:
Boy, the time of day you mention does pose a potential challenge. My suggestions are to:
* Keep students actively moving around (lab, practice, skills, etc)
* Frequently reference the real world or work setting they're being prepared for.
* Stimulate their minds to keep them focused; ask questions, have students demonstrate what they know, thing along these lines
* Limit any activity to 20 minutes. After that, move to another activity, or at least another media to present the material. This will help keep students focused.
* Anything that is lecture oriented has to have flipcharts, PPT, overheads, or discussion
* Use colored paper for handouts; use contrasting colors and appropriate formating with PPT's; avoid giving handouts with small print. This should reserved for when their eyes ae rested.
* Finally, take time to just talk, about the profession, personal lives, stories, past situations, or plans students have related to what you're currently teaching.
Good luck!
Regards, Barry