When making the bubble liquid, you should aim for the following mixture: 16 parts distilled water (lead acid battery water or such), 4 parts concentrated washing up liquid (if the tensides are diluted with water, as they are in cheap alternatives, you have to adjust the amount you use upwards) and finally 1 part glycerine. This is, not unexpectedly, roughly the ratios that all living cells have in their membranes, and therefore (as nature is good at optimizing things) it makes for a very stable bi-layer (scientific name for the skin of the soap-bubble) Easy to remember too 16:4:1. Let the mix sit for at least two days, as it gets more stable with time. On sunny days, if you make large bubbbles, they will lift from the heated air inside, like hot-air baloons. Which is cool (or hot).
YES!! this is amazing! It is so important to get children interested in science. I hope you don't mind if I share this and do my own bubble experiment; I'll just have to find a way to relate it to God :)
