Ninth Grade Geometry

Instructor: Patty Armstrong

Curriculum Map, Class Page

In Geometry, students examine how reasoning and logic enable members of a society to make civilized decisions. The students learn how to prove a hypothesis by induction and deduction. They analyze the logic used in advertising slogans. Students also study architecture and examine the impact that geometry has on the architecture of a civilization. In particular, they compare and contrast the architectural styles of two well-known American architects.

Students learn how geometric knowledge, which includes definitions, formulas, postulates, and theorems, is useful in the everyday lives of people living in modern civilizations. They apply this knowledge in designing a quilt sample. They also use self-similarity and iteration to create a fractal pop-up card.

Finally, students investigate how geometric constructions, ratios, and proportions help people to solve problems in a civilized society. They analyze information and make a recommendation on the purchase of a plot of land. They apply solar geometry by using triangles and trigonometry to design an efficient solar home. In their final project, they model Cavalieri’s Principle by comparing the volumes of a sphere, cylinder, and two cones by comparing cross sections of the objects.

Students consider the following questions:

• How do reasoning and logic enable a society to analyze information inductively and deductively and then use this analysis to make civilized and educated decisions? What impact does geometry have on the architecture of a civilization?
• How is geometric knowledge useful in the everyday lives of people living in modern civilizations?
• How do geometric constructions, ratios, and proportions help people to solve problems in a civilized society?