Solar Air Tube

So today was "Craft Wednesday" but I've been wanting to try this: http://www.solar-balloons.com/ht_tube.html for a long time and thought it would be a fun experiment. So it turned into "Slip-and-Slide-Seed-Spitting-Science Wednesday" instead. Because I'm the director of this here day camp. I get to decide. It was over 100 today, though the sun wasn't very direct this afternoon.
The hardest part of the whole experiment was finding cheap enough trash bags- seems every one's concerned about quality or something, and having trash bags that are strong and durable and its almost impossible to find thin (<.5mm) black plastic bags. We went to three stores and finally bought the last box of thin bags at the dollar store. Really, I can't imagine what you'd use these bags for other than experiments like this- you can barely hold them without tearing them! The kids thought it was lying that the company was called "TUF" but finally decided it wasn't really lying, since they spelled it wrong on purpose, but it still wasn't fair, because some people might not notice or even know how "tough" is supposed to be spelled. Because true and not true isn't about spelling things right or wrong!
Our tube wasn't quite this long- we had six bags instead of eight. We didn't get a lot of height, but there were times this afternoon the tube was on end, floating around. Thank you kind neighbor with a big sunny patch in the front who didn't mind a whole pack of wet swimsuited kids running and hollering and chasing a garbage bag tube around all afternoon! The highlight was when they tackled it and jumped on it and popped the poor thing.
Then asked when we could make another one!