Discovering Similar Triangles

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SWBAT identify and determine key properties of similar figures

Big Idea

Completing a hands-on activity, students will cut, categorize and discover properties of similar triangles.

Lucky Charms Practice

30 minutes

The Lucky Charm notes for this lesson provide a review of ratios and proportions to introduce the new unit.  These skills are necessary for students to have a strong mastery of prior to starting the similar triangles unit. 

The Lucky Charms video provides an engaging way to start review of ratios by answering an age old question about of how many marshmallows and oat pieces there are in a box of this cereal. 

Students can then work through the review on ratios and proportions with real-world examples. 

This review will prepare students, in the exploration section of class, to look for repeated reasoning (MP 8) and also will  be able to use the models in the exploration to identify key properties of similar shapes (MP 4). 

Similar Triangle Hands On Exploration

40 minutes

Activity/Homework and Exit Ticket

10 minutes

An Activity-Homework has been included for this day of class, however, students will most likely not be finished with the Exploration activity.  This means that students will only be able to complete question #6 of the activity.  You may want to give students a review assignment focused on proportions, which could include practice problems from this review website.

The Exit Ticket provides you with information about students' progress in the exploration.  This should be a handed-in assigment.