For a once-weekly class taught to international learners of German, what recommendations can you give me.
Three to four students (but sometimes only two or one). 60 minutes per class. Diverse international clientele (people from North America, Asia, Latin America) but all from the same company. On site at client's office. White board, beamer available. Beginners (some with minimal prior learning). Frequency cannot be increased beyond 1x weekly.
Instructor can assign homework but there is no guarantee that students will get around to it (all work 70-80-hour workweeks).
Books / audiotapes / computer-based learning / exercises. Tell me what works!