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Lesson plan

Duct Tape Bracelets: Analyzing a proportional relationship with like units and compute the missing side length by using a scale factor

teaches Common Core State Standards 7.G.A.1 http://corestandards.org/Math/Content/7/G/A/1
teaches Common Core State Standards 7.RP.A.1 http://corestandards.org/Math/Content/7/RP/A/1
teaches Common Core State Standards MP5 http://corestandards.org/Math/Practice/MP5

Duct Tape Bracelets: Analyzing a proportional relationship with like units and compute the missing side length by using a scale factor

This lesson builds on students understanding of proportional relationships in similar figures. Students find the missing side length of similar rectangles. Students will develop an understanding of how scale factors less than one and greater than one affect the length and width of a rectangle. This builds towards solving problems involving scale drawings of geometric figures, as well as working with ratios using fractional amounts and multiplying and dividing rational numbers. Big Ideas: Corresponding parts of similar figures are proportional and have a multiplicative relationship. Missing lengths of similar figures can be computed by multiplying or dividing by a scale factor. Vocabulary: corresponding, scale factor, similar figures Special Materials: Tape Measure or ruler and string 1/4 inch graph paper