As Christmas approaches, I'm thinking of what trick I can perform for our dinner guests this year. Previous tricks include making water boil at less than 100°C, (not) burning a £10 note and making fast-food ice cream using liquid nitrogen. It's great fun and always results in our guests talking about science. I feature demonstrations in my own work and so I'm always on the hunt for new ideas.
By happy coincidence, the British Science Association  has launched the first stage of Get Set... Demonstrate : A nationwide search for the most exciting, thought-provoking and wow-factor inducing science demonstrations. I think I've covered the principle adjectives there. As a former teacher turned presenter, researching a new demonstration, practising and refining it remains an essential aspect of my own professional development. It opens the mind to alternative ways of communicating and explaining scientific concepts. Furthermore, I really enjoy watching new takes on old ideas; different teachers and presenters often have their own interpretations of well-known demos.
How was it for you?
I'm sure you can recall a memorable demonstration from your own school days. For me, it was the exothermic reaction of hydrogen an oxygen in a 4 pint plastic milk bottle. I was in Year 8 at the time and I remember being on the edge of my seat, filled with the anticipation of the loud bang alone.
And that's my point: You remember the ones that excite and make you think.
Demonstrations can become second-nature to regular performers, but it is important to keep them fresh and slick. If you just bang out (no pun intended) demonstrations in a routine manner, they risk becoming passionless and dull. They lose impact. They are inherently great fun, and it is important to let your enjoyment and enthusiasm shine through. Having said that, demonstrations are more than just about having fun... They are about communicating science in a visual and, quite often, aural manner.
I'll be honest that as a teacher, I was always at my best when doing a demonstration. I think it is the performance aspect that really appeals to me, as well as it being an invaluable tool for helping audiences to visualise a particular scientific effect or phenomenon.
Size doesn't matter
A small demonstration  can be just as inspiring as a larger one . I've had some absolutely spectacular results and embarrassing failures on a variety of scales. I'll never forget the technician that supplied me with magic snow instead of soap detergent for a Ultra-Violet light demo. Nothing fluoresced, but there was an impressive growing snowdrift in front of me.
Practice makes perfect
My single most important piece of advice regarding any science demonstration is to practise. A demonstration should always be practised before showcasing it to a live audience. I cannot emphasise this enough. Not only does this enable you to see how long it takes or to master the set-up, but it also allows you to build up confidence, particularly if it is a demonstration involving a loud bang, a flash or something breaking. What's more, familiarity allows you to shift your focus towards other aspects of the demonstration, such as your language or timing finesse.
Poor aim - a word of caution
Even well-rehearsed demos can go wrong. Several years ago, I blew a hole in the ceiling of a brand new classroom when a bottle-rocket ricocheted off a retort clamp into the roof cavity. It was entirely my fault for not aiming it correctly and I guess learned the hard way. I can still picture the children's faces and the light-fitting swinging in my peripheral vision. It wasn't one of my better moments in the classroom, although I occasionally get stopped in the street by ex-pupils who continue to thank me for such a memorable lesson.
Demonstrations are not just about bangs. Yes, the thrill and the excitement can create a great atmosphere, but there is so much more to science. A classic favourite of mine is the wrecking ball , silent and absolutely terrifying for a first-time volunteer, especially if they keep their eyes open!
If you are looking for interesting demonstration ideas, then why not have a look at the Get Set... Demonstrate YouTube channel ? This is where all the nominations on YouTube will be posted. If you know of a good demo, then tell us about it via the nomination form .
I am really looking forward to seeing the nomination list grow and, as I continue my quest to find a new Christmas dinner trick, please remember:
A demonstration is for life, not just for Christmas.
Science presenter, pyrotechnician and education consultant