National Science Week has come and gone for another year. This year, I spent a lot of it down at Canterbury Public School where I am their tamed scientist as part of CSIRO's Scientists in Schools program. It was a lot of fun, and we walked away with a world record - more on that in a bit. Here's some of the cool stuff we did: Above is my box of household products for various experiments, and the results of cabbage indicator. Cabbage indicator is made by simply boiling purple cabbage. The resultant solution contains a chemical called anthocyanin which exists in an equilibrium of three forms depending on the ph, allowing a wide range of colours. We used mould remover (strong base), window cleaner (mild base), lemon juice, vinegar and tartaric acid (mild acids).We've made corn flour slime before, but if you make it with tonic water, it will fluoresce under UV light and glow in the dark. Tonic water contains quinine, which apart from fluorescing, is also a preventative for malaria (which is why it was put in tonic water in the first place). And here's some phosphorescence:None of the kids had seen an overhead projector before. This demonstrated some basic optics regarding mirrors and light travelling in a straight line, as well as how old I now am. The food colouring / milk / detergent experiment works in the same way our detergent-powered boat works, noting that the fat in the milk helps keep the food colouring separate (it doesn't readily dissolve until the soap is added). Liquid nitrogen is always good (as was the liquid N2 ice cream we made), as is entertaining your local MP and making a homemade periscope.And on that world record, we participated in the world record stargazing attempt for most number of people gazing at the stars at once across many sites. And we got there (unofficially at the time of writing anyway). It was dark, I didn't get many shots, but I did get this one of our planetarium and star demonstrator...