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Similar Triangles Activity

similar triangles activity


  • Triangle sheets, pages 127-130 (1 set per student)

  • Scissors (1 per student)

  • 12" x 18" construction paper (1 sheet per student)

  • Glue sticks (1 per student)

  • The completed project prepared by the teacher before the lesson


This project teaches students to identify similar triangles. It also teaches them how to test for similarity by placing shapes inside one another.

The teacher should start the lesson by drawing two similar triangles on the board (the teacher should practice this beforehand if need be). Ask students “are these triangles the same?” Try to elicit a response such as “they are the same shape but different sizes.” Explain further that similar triangles are triangles that have equal angles but not equal sides. This is different than congruent triangles, which are exactly the same. The teacher can further clarify by drawing examples on the board:

similar triangles activity 2

Get the entire lesson!
activity book