Task 5

Materials and tools for a working group: 

coin, 2 mirrors

The teacher begins the educational situation by suggesting an activity in which pupils observe how the image of the coin in the mirror is created. Their task is to put two mirrors together and put a coin between the two mirrors (see Task 5a). First, they spontaneously observe how many coin images will appear in both mirrors. The number is written to the first column. Then the teacher directs the pupils to try to put the mirrors closer together (as shown in the second column in the table; they still touch the edge) and re-count how many coin images they see in both mirrors. After counting, they generalize the conclusion about when we see more and when less coins.

Consequently, the teacher can lead the pupils to try to work with the situation to get even more coin images in the mirrors (task 5b). Pupils draw the position of mirrors and coins when they have acquired the most images of coins in mirrors and compare this situation to those examined in task 5a. At the same time, the teacher inspires pupils to study more precisely by asking other questions to determine whether the amount of coin images in mirrors depends on the coin size and/or the size of one or both mirrors. The results of the examination are recorded in groups in the table in task 5b in the form of a conclusion. They compare the results between groups. The teacher then asks if all the coins observed are images of the same reality.

These two tasks are followed by a third one, in which the teacher encourages the pupils to try to draw a hypothetical situation based on the results of the examination of previous tasks, where an infinite number of coin images could be created in two mirrors. In addition to designing mirrors, it is the task of pupils to justify their predictions by logical reasoning based on what they have learned about this (For example, pupils can claim that mirrors will reflect the coin indefinitely when they are facing each other, ie when they are parallel to each other) and the coin will be between them, for example, in the hairdressing industry, where they saw their picture in two mirrors placed on opposite walls of the room.). Finally, the teacher discusses with pupils how to see as many single coin images in two mirrors, knowing that we can only create one coin image at a time with one mirror (two should only be able to create two coin images).

The fifth task is in principle aimed at developing a precise investigation by observing a simple reality. In this way, we develop an attitude towards exploring the commonly observed phenomena – pupils get the notion that the phenomena that surround us are still interesting to explore and something new can always be found about them.