Task 4

Materials and tools for a working group:

• 2dcl or 3dcl plastic cups (10pcs), sting, thread, wire, rubber band (eg hat), wool, scale, scissors

Pupils can also examine the findings of task 3 in task 4, or the task 4 can be perceived as an alternative approach to the development of the same idea of spreading sound through different materials. In the fourth task, the pupils first create a „string phone“ using string and two plastic cups. Pupils find that if the string is straight, it works, which means that the string is transferred from one cup to another. This part of the activity is, in principle, a stimulating situation that confirms what pupils have found in the previous investigation. The research challenge is to find out what would be possible to replace the string in order to make the phone work better (i.e. to make the transmitted sound clearer and louder).

Pupils make predictions about the different kinds of substitutes for string. If they also performed task 3, they justify the creation of predictions as a result of the examination of the third task. If they did not implement the third task, the predictions justify previous experience.

After making the predictions, the pupils are dedicated to its verification. The teacher makes sure that the correct conditions of experimentation are observed. This means that if pupils want to compare which of the two materials is more suitable for the creation of a string phone, they must create two phones that differ only in the quality of the string (they are made of the same containers, the same way, the only difference is string quality). Both phones are in their hands and use them alternately, preferably by the same ear. Precision is a typical characteristic of a scientific approach to the research we want and can develop in this age. They record the results in the verification section and formulate a conclusion based on these results. Part of the conclusion is the answer to the question of what features should the string, which transmits sound better.