We've already committed to running the course again next year, for the Air Cadets (and any St. John Ambulance cadets who didn't attend this year but still want the proficiency badge). I think I'll do as Chris suggests and use it (the Zip-lock, cup and upside-down funnel) as a training aid - it seems to me it's exactly the type of thing that kids that age will have fun doing. But I'll practice with it to see how well it works, first.<br><br>Chris, is your complaint with the solar still about the whole concept, or is it just the notion of water evaporating from the earth? In other words, do you think the solar still is effective as a means of purifying salt or contaminated water, or are there better ways of doing this?<br><br>