MP8: The Medians of a Triangle

15 Aug

How do you give students the opportunity to practice “I can look for and express regularity in repeated reasoning”?

SMP8 #LL2LU Gough-Wilson

When we have a new type of problem to think about, I am learning to have students estimate the answer first.

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I asked for their estimate in two slightly different problems because I wanted them to pay attention to what was given and what was asked for.

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Students then interacted with dynamic geometry software.


What changes? What stays the same?

Do you see a pattern?
What conjecture can you make about the relationship between a median of a triangle and its segments partitioned by the centroid?

As students moved the vertices of the triangle, the automatic data capture feature of TI-Nspire collected the measurements in a spreadsheet.


I sent another poll.

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And then we confirmed student conjectures on the spreadsheet.

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And so the journey to make the Math Practices our habitual practice in learning mathematics continues …

1 Comment

Posted by on August 15, 2016 in Angles & Triangles, Geometry


Tags: , , , , , ,

One response to “MP8: The Medians of a Triangle

  1. howardat58

    August 15, 2016 at 9:26 pm

    Now balance the triangle on its centroid. This will get them thinking!


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