Milan's concern is that in schools we tend to focus on textbook tasks that can be solved by most children using methods that are prescribed by the teacher. I think that this is true in British schools as much as in Czech schools. He set out to devise some geometric tasks in which the student does not know the solving method but can discover it for him/herself or in which he/she knows the method but does not realise that it is suitable for the new problem. At NRICH, these are just the kind of problems that we are interested in and write for the website.
Looking at Milan's ideas for problems, and arenas in which problems could be devised, I was struck by the richness of the scenarios that he had chosen and also the quality of mathematical thinking that some simple contexts were capable of provoking. Milan stresses his desire to devise problems that will motivate children and engage them as well as extend their mathematical thinking and develop their imaginations. The idea is to present settings in which there is no obvious method but in which children can be encouraged to think deeply about the context and extend their ability to think mathematically, especially geometrically. So what do these scenarios look like? The list is extensive and I do not have the space in this article to show you all Milan's ideas but here are a few to give you a taster.
Milan suggests placing a die on a square grid and recording the top number. The die is then turned onto one of the other faces. Then the top number is recorded again. We developed this idea into a game called Roll the Dice. Try it yourselves! It is quite surprising and counter intuitive. Can you explain why it works as it does? The children we have used the activity with, are fascinated by the idea and, as well as asking for reasoning and justification, the task helps to develop recording skills and systematic approaches to possibilities. I think we are possibly getting better at encouraging these kinds of thinking in the context of number work but in shape and space we do tend to be prescriptive. This problem offers us a geometric context in which to develop mathematical thinking.
Other suggestions include looking at routes through squared grids using colour, say red for right and blue for up, so that different paths can be described by colours simulating the real movement of an object, a person through streets for example. This could be extended to include forward and backward movement and possibly linked with number so that a move to the right horizontally involves adding one and a move vertically upwards involves adding five. This idea was developed into a problem called Routes 1 and 5.
Milan Trch and Eva Zapotilova, (1995), Non-standard Problems: The Means of Development of Thinking and Geometric Imagination in The Lowest School Age. Proceedings of the International Symposium on Elementary Maths Teaching 1995. Charles University, Praha, Czech Republic.
Milan Trch and Eva Zapotilova, (1997), Non-Traditional Mathematical Tasks as a Means of Developing Mathematical Thinking of Younger Children and Problems with their Evaluation. Proceedings of the International Symposium on Elementary Maths Teaching 1997 . Charles University, Praha, Czech Republic.
This article appeared in Primary Mathematics, a journal published by the Mathematics Association , in Summer 2002.