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Geometry and early algebra: attributes, function machines, and sorting

Other Presenter(s): 
Kate Coleman
Other Presenter(s): 
Tracy Manousaridis
Other Presenter(s): 
Samantha Lowe
Meeting: 
NCTM Annual Meeting
Date: 
April 14, 2011
Location: 
Indianapolis, Indiana

By sorting non-standard as well as garden-variety geometric shapes, children see enough contrast to recognize what features make particular shapes special. Other fun activities connect elementary school geometry with early algebraic ideas and build a robust interconnected mathematics. See classroom video and take home activities for your students.

Participants will engage in and take home classroom-tested elementary school activities that bring out deep mathematical ideas. This presentation also shows teachers the power of extreme examples and near-miss non-examples, and how sorting and classifying activities can help children literally sort out their mathematical ideas. One style of activity, in which the teacher remains silent, rivets students’ attention as they must watch for clues and listen to each others’ conjectures.

Classifying is natural, part of how we construct categories and learn language; mathematics adds the refinement of articulating and then reasoning about attributes and relationships among them, creating matching rules (e.g., functions) and building yet new categories from the results. We will show, with video and activities, how children do this.