MP8: The Medians of a Triangle

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

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

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.

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.

And then we confirmed student conjectures on the spreadsheet.

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