Stick with your best ideas
You might not think that young people needed a slime kit but, in the science laboratory at Rickmansworth school, a Hertfordshire comprehensive, they have one and it is proving very useful. Slime, as it is created at this school, "has remarkable properties", says teacher Gordon Gentry. It will pour, creep and even snap if you pull it sharply. It will shatter if you hit it. It is exactly the kind of thing you need to teach key stage 4 children about the nature of investigations.
The recipe for slime has been around for some time but it was the teachers at Rickmansworth who decided to develop it and make a kit providing the chemicals and outlining experiments in which students can investigate how changes in concentration, temperature and pH can visibly change the sliminess of slime. "It is incredibly motivating," says Gordon Gentry.
Slime is one of 20 ideas and products now available from the teacher associates programme of the Science Enhancement Programme, a project funded by a charity, the Gatsby Technical Education Project. The project aims to look at the place of practical work in enhancing interest and attainment - especially in physics and chemistry at secondary schools.
What the programme does is free up money and time for teachers to develop products and ideas, which are then offered to school on a non-profit basis. You have an idea that you feel would be useful for other schools as well as your own. You submit it to the SEP and, if it satisfies the criteria, they will make provision for the school to replace you for up to one day a week for a year while you develop it. You will also get funds for new equipment and some financial support.
"Many teachers feel the ideas they come up with are not commercially viable but would still be very useful to other teachers," says Martin Loftus, who is on secondment to the project from Notre Dame high school in Norwich. "They are interested because the project is organised by other teachers and is a charity. We're not looking to make money, we want the ideas to be useful and to find their way into schools."
To make slime, for example, schools would have to spend a lot on chemicals that often can only be bought in large quantities. SEP has bought "loads of the stuff", says Gordon Gentry, and put it into the kits together with the ideas for experiments. The price is pound;5, which provides sufficient for wo whole-class experiments.
Mr Gentry is now investigating how to extend the use of microscale chemistry in post-16 courses. This does away with the wasteful, time-consuming and environmentally unfriendly process by which A-level pupils carry out organic synthesis using large quantities of material that is later thrown away.
Another simple idea is a card game to give sixth-formers practice in constructing nuclear equations. Based on gin rummy, it has radioactive symbols instead of the traditional icons.
Submissions do not have to be products; ideas which are fully explained and developed are accepted. For example, Using Video Capture to Enhance Physics Practical Work is a booklet by Simon Pugh Jones, a teacher at Writhington school, Somerset, in which he shows how the use of video can enhance practical work.
The project is developing a list of criteria teachers can use to assess the usefulness and relevance of their practical work.
Further details about the Science Enhancement Programme from: The Gatsby Technical Educational Project,47 Red Lion Court, London EC4A 3EN. Tel: 020 7936 3759 E-mail: Yvonne.firstname.lastname@example.org Website: www.sep.org.uk
HOW TO MAKE SLIME.
STUDENTS are provided with 25ml of 4 per cent PVA and 5ml of 4 per cent Borax solutions. The procedure will produce sufficient quantities for four batches of slime.
PVA solution: Heat 100ml of water to about 90oC. It is important that this temperature is not exceeded. Using a magnetic stirrer, slowly add 4g of PVA. If the PVA is added too quickly it will not disperse without difficulty. PVA solution can be made without the magnetic stirrer but that is much more time consuming. Maintain the temperature and keep stirring until the PVA dissolves. Pour into measuring cylinder and top up to 100ml to replace water lost by evaporation. Allow to cool.
Borax solution: Dissolve 0.8g of borax (sodium borate) in 20ml of water. A small amount of water soluble dye (for example, fluorescein) or food colouring can be added at this stage. Only a very small amount of fluorescein is needed. Increase or decrease quantities as desired. The best slime is made by mixing PVA and Borax in a 5:1 ratio.
Place PVA solution in a beaker and add the appropriate amount of borax. Stir rapidly with a glass rod to ensure total mixing. Within seconds the slime forms. Allow to stand for a few minutes while the cross linking continues. Your slime is now ready for use.