Interactive Primary Newsletter 33 Pop-up Pals

Jack-in-the-Box design Jack-in-the-box was originally a name for a sharp or cheat, “who deceived tradesmen by substituting empty boxes for others full of money” [Robert Nares, A Glossary of Words, Phrases, Names, and Allusions, London, 1905 - see the Online Etymology Dictionary]. For a more traditional type of pop-up, such as that built at Kinross, it is often difficult to muster enough resources to cover all of the ideas that the pupils will come up with. Springs are a particular problem; they must be strong enough to carry the puppet but not so strong as to demolish the box. However, are ‘real’ springs needed? There are balloons, folded paper, rubber bands, plastic and numerous other things the pupils will discover that can be used instead of a spring.                Figure 6a - Matchstick end fixing                                Figure 6b- Rubber band 'spring' A rubber band can be a very effective substitute for a spring in a Jack-in-the-box. If this type of ‘spring’ is chosen it is essential that a strong cardboard box is selected if collapse is to be avoided. Figures 6a & 6b shows the method of fixing a rubber band to a box using spent matchsticks or cocktail sticks. We found this method easier and more reliable than tying a knot. What about the Jack? Ideally this should be constructed from a strong but relatively light material. When using a rubber band as a spring remember that the design of the Jack must allow it to be balanced on what is a very narrow moving strip. An effective Jack can be made from the inner cardboard core of a kitchen or toilet roll. To get one of these to balance on a rubber band, try cutting two slots on opposite sides of one end of the roll. This will help, but it can still be very frustrating trying to get the Jack to stay in place, particularly if a square box is used. We found it easier to use cylindrical cartons rather than the more traditional square cardboard box for our Jack-in-the-boxes. It can still be a fiddly process getting the Jack in place but once in place these cylinders provide very good support for the Jack. Figure 7 shows a well known cylindrical carton with an equally well known drinks-can used as a Jack. Figure 7 - Crisps ’n Cola can Jack-in-the-Box “Horrible Science” magazine - a health warning