Making School Science Exciting – and encouraging good hygiene practices!
I was asked to run a science class at a local school for 40 Year 5 children (aged 9-10). Using an ultra-violet light torch and glow-in-the-dark powder, we carried out 3 experiments to bring microbiology to life and show how invisible organisms can spread. Some of the children had seen me doing something very similar on GMTV in the summer.
Bacteria are Invisible, but they are Everywhere
First I explained that you can’t see bacteria and viruses with the naked eye, and that whilst most micro-organisms are harmless, some can cause illness, and these are called pathogens. Our experiments were to demonstrate how bacteria and viruses could spread. Because the powder is invisible in bright light, it is very useful to show how invisible micro-organisms can transfer from hand to hand or surface to surface around the home.
Group one was asked to form a line and the first girl shook my hand, then turned round and shook the hand of the girl behind and so on to the end. Then we dimmed the lights and using the torch we could see the spread of the powder from one girl to the next. This demonstrated how germs could spread via hands. The powder was still visible on the 7th hand! Obviously the importance of hand-washing was becoming evident….
Group 2 used a tea towel to wipe dry some wet drinking beakers. What they didn’t know is that I had put some of the powder on the tea towel! When we shone the torch on the cups, the powder could be seen on the inside of the cups. This showed how important it is to wash the tea towel regularly so that you are not putting bacteria onto your clean crockery and cutlery when drying up.
Cleaning – can make things Dirtier!
Group 3 were asked to go and “clean” some surfaces in the classroom with a cloth – and guess what? There was some glow in the dark powder on the cloth too. So when we shone the torch on the surfaces, we saw how the powder had transferred to surfaces. This demonstrated how dangerous a dirty cloth could be. I told them about all the dirty cloths we found in the UK survey, many of them with E.coli on.
Group 4 used the “green is clean” swab to see if there were any dirty areas in the toilets and classroom – but well done school cleaners – all was sparkling!!
Finally, as the powder was now on nearly everyone’s hands, I played a little trick, and asked everyone to go and wash their hands. Then I used the torch to see who had done it properly – oh dear! We then had a discussion on how to make sure that the backs of hands are washed, between the fingers and nails. The time it takes to sing “happy birthday to you” all the way through twice is how long you should take. So I guess it will be quite noisy at the sinks now – sorry teachers!!
We then gave out homework sheets and one task was to invent a bug, draw a picture of it and give it a name.
Teachers: For a session plan and UV powder and a torch contact us: firstname.lastname@example.org