Figure 9: Video of class discussion comparing exponential decay to inverse variation from Growing, Growing, Growing

This video shows students discussing their work on Problem 4.1 in Growing, Growing, Growing that introduces students to exponential decay. During the "explore" phase several groups of students conjectured that this relationship is like the inverse variation situations they studied earlier in the year. The video segment shows the part of the class summary where this conjecture is discussed and proved wrong.

Task used in Figure 9
Lappan, G., Phillips, E. (2009) A Designer Speaks. Educational Designer, 1(3).
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