This post is a follow-up to the original iLesson “iClassify Triangles“. The original lesson provides a few direct instruction videos on classifying triangles, a set of mystery triangle flash cards, and a handful of extension app-tivities. The following could be used as a stand-alone geometry resource or an additional app-tivity to support the initial iLesson.

**Student Task**: Use the Geoboard app to make an example triangle for each of the following triangles using the specified color:

**Yellow:**obtuse isosceles**Red:**scalene right**Purple:**right isosceles**White:**acute scalene**Green:**acute isosceles**Orange:**obtuse scalene

**Extensions**: Complete the question and one of the tasks below.

**Question**: Which triangle can you not make and why?*acute equilateral***Task 1**: Take a screenshot and bring the completed Geoboard image up in Skitch. Calculate the perimeter and area of each of the triangles.**Task 2**: Graph triangles in Geometry Pad. (Teacher could provide a task card with specific directions: e.g. “graph an isosceles right triangle in quadrant 2”).

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