@article{oai:aue.repo.nii.ac.jp:00003127,
 author = {飯島, 康之},
 journal = {教科開発学論集},
 month = {Mar},
 note = {text, 筆者が開発した作図ツールGC/html5 で実装しているマルチタッチは、iPad 上のSafari などでの標準的なピンチ操作を禁止する代わりに、複数の点を動かすことなどを実現している。図形を動かして調べる数学的探究の中で、作りたい種類の四角形そのものを意識化して複数の点を動かしたり、表現したい図の動きを指の動きで補完的に表現することで概略的な理解をしたり、図形の中の関係を保つ動かし方を意識化することで数学的な問題も生み出せることを例示した。また、Varignon の問題と2円と2直線の交点でできる2種類の四角形の関係の問題に関する授業実践を例示し、複数の点を動かすことは生徒にとって適切であると同時に、指タッチはグループ活動の中での協同作業に適していたことや、特にVarignon の問題では、動かし方と図形の性質に関する議論がグループの中で活発に行われたことを例示した。, The author have developed one of the dynamic geometry software GC/html5 since 2010, which can be used with multi-touch control. The standard gestures including pinch, which are used under the browser Safari for iOS, sometimes disturb the user's mathematical inquiry. Under GC/html5, they are prohibited, and user can move some points of figure simultaneously. Following activities can be identified by moving point simultaneously with multi-touch; (1) we can deform figure to the supposed state quickly (e.g. from rectangle to rhombus), (2) to understand and inquire the problem in which some points move under some conditions, we can use the general figure to move their point with multi-touch, and (3) we can discuss about how to move points of figure, in order to maintain some conditions about the figure, and in some case, we can find out new mathematical problems. As the typical examples, we discuss about the Varignon’s Problem (ABCD is a quadrilateral and E,F,G,H are the midpoints of AB,BC,CD,DA respectively. Inquire the relation of ABCD and EFGH.) and the problem about how to move two points of quadrilateral keeping the class of original figure (parallelogram, rectangle, rhombus, kite and isosceles trapezoid). And, in this paper, we report the outline of two classroom activities and analyze them. One is about the Varignon’s problem including the problem about how to move two points of ABCD to maintain the EFGH square. The other is about the relation of two quadrilaterals which are formed by the intersection s of two circles and two lines.},
 pages = {85--94},
 title = {作図ツールGC/html5 のマルチタッチ機能を生かした数学的探究と授業の実際について},
 volume = {2},
 year = {2014}
}