Teacher Comment

Mr. Tanaka’s Post-Lesson Discussion Opening Statement I am Tanaka here at University of Tsukuba Attached Elementary School. It is nice to meet you. Thank you for coming and observing my lesson. Usually, the lessons on area are a part of quantities and measurement, but there could also be interesting side-benefits to learning about geometric shapes. In the lesson about geometric figures at the middle-school level, the concept of area is used as a tool in proofs. This is because the explanation using figures helps to cultivate and strengthen thstudent’s logical thinking. I think it would be a shame if the 4 -grade area lessons covered only counting the number of units that fill in a space and finding area by developing formulae for rectangles or squares. There are many interesting rules about equal-area figures if you look at the figures differently. For example, like in today’s lesson about perimeter, there are many fascinating aspects. This is a study of investigating changes of one element when the other element is fixed. The elements to study could be reversed. You could fix the perimeter and investigate the areas. That could bring up interesting rules. I first planned to use Pick’s Theorem for today’s lesson, that is, investigating areas with a given number of dots or investigating numbers in dots with a given area. But then, the point of the lesson would be investigating functional changes with given areas. The objective of my ...