Twenty years ago when the author was student teaching, he quickly learned what geometry teachers and researchers (e.g., Senk 1985) have long known: High school geometry students struggle with proof. Throughout his career, he has tried to create instructional materials to make proof more accessible to his students. From field-testing materials with…

Provided is an analysis of Turtle Geometry using van Hiele levels of development and understanding. The author also relates a language use framework, suggested by the work of Fry (1982), to the language activities of Turtle Geometry. Research supporting the analysis is discussed. (RH)

This teacher's guide is the ninth in a set of 20 activity booklets for teaching mathematics to children in grades 1-8. The 20-level curriculum embodies carefully delineated areas of learning arranged in progressive stages, eliminating grade restrictions and permitting continuous growth according to the individual's ability and rate of learning.…

The mathematics curriculum provides a framework of instruction for exceptional child education in grades K-12. Content areas include: numeration, whole numbers, rational numbers, real/complex numbers, calculator literacy, measurement, geometry, statistics, functions/relations, computer literacy, and pre-algebra. The guide is organized by content…