It's a shame you're so far away because if you were closer I'd be more than happy to come to your workshop intermittently and work with you. I mention this because very occasionally I get such contracts. A typical example is similar to your description of a box making exercise whereby the person that engaged me had a cabinet building project. About every two to four weeks I'd go to his workshop and help him with all the tasks needed to build a solid wood free standing cabinet with several drawers and drawers bottoms that had to be veneered. Naturally, such a project offers many opportunities to demonstrate the necessary skills, and for him to practice them whilst I supervised and offered corrective guidance. In conjunction with helping him develop those skills there are plenty of opportunities to demonstrate everything from using a bench saw properly, to machine planing, tuning and sharpening hand planes and so on.
In between my mentoring visits my mentee got on with practicing the skills taught, and sometimes got into a bit of a hash with them meaning here was yet another opportunity, i.e., the one showing the 'how to get out of a hole' lesson, ha, ha. For this kind of mentoring role I have a day rate with a minimum half day charge, plus travel expenses if I have to travel more than a fifty mile round trip. My day rate covers anywhere between about seven hours up to about nine. The reason for the day rate is simply that it's not worth the palaver to me to do this kind of thing by the hour, so day rate it is. Slainte.