Task 13

Materials and tools for a working group:

skewers, wooden sticks, pins, plastic spoons, plasticine, rubber bands of different sizes, adhesive tape or hot pistol

In previous tasks, pupils explored how objects fall to the ground when they are fired in different directions and differently forced, and how the fall is affected by the shape of the object being thrown. First, the teacher summarizes what they already have discovered and starts discussing how people have used this information in the past. It can also only directly follow up on the twelfth task and recall the historic object throwing device – the catapult. He can show historical catapults to pupils or discuss with their pupils their experience with the catapult (whether they have seen them, heard about them, noticed them in historical movies, in museums, or in fairy tales). Then he suggests pupils to try to construct their own small but functional catapult model that can be used to shoot the polystyrene spheres they used in their previous tasks so that they can continue as far as possible (technical challenge).

The teacher will show the pupils the tools using which they will try to build the catapult (skewers, wooden spatulas, pegs, plastic spoons, plasticine, rubber bands of different sizes, adhesive tape or hot pistol). Teacher encourages pupils to look carefully at the drawing of the catapult in task 13 and asks them to propose the simplest version of functional catapult while using only the materials available, thus pupils should have a possibility to observe the materials and tools.

During designing the teacher lead the pupils to consider what they already know about shooting objects and how to get bullets as far as possible. A classic, sophisticated technical solution builds on a natural understanding of how the phenomenon behaves in different conditions. The teacher should avoid pupils to use trial and error method at this stage. Intuitive solutions are also interesting in the development of technical education, but this taskis deliberately included in the research of oblique litter and therefore it would be interesting to exploit the potential of acquired knowledge in previous research tasks. This will foster the pragmatic importance of science knowledge (the development of the notion of science; the 13th Big Idea of Science). Pupils can present their designs or try to construct them immediately. The discussion is very fruitful for making the proposals thought out. Further pupils create a catapult prototype according to their own design/proposal. They are likely to find themselves, at the very design stage, that not everything can be constructed as intended, thus teacher encourage them to make intuitive changes in the initial proposal.

Since the catapult had to be created (according to the call) in such a way that the fired object would hit the ground as far as possible, the pupils will verify the success of the catapult construction by comparing distances reached by catapults constructed in different groups. The winning catapult is then an object of further investigation – pupils try to judge what makes this one the best one. By comparing, but also observing precisely how the catapult behaved when firing a ball, groups can adjust their catapults and try again. It is the changes that pupils made to their prototypes that are the basis for the conclusion in which pupils find out how the catapult needs to be constructed (which is essential to the structure) so that the object reaches as far as possible.