Students learned where the area formula for triangles comes from. Students were told to draw a rectangle and then draw a diagonal line segment. They realized quickly that a rectangle is made of 2 triangles. They then were given dimensions of the rectangle and calculated the area.
I asked the following question:
"If you know the area for the rectangle is 48, what do you believe the area of each triangle to be?"
Students were very quick to say the area of each triangle would be 24. Most students were able to explain this very well. I think this is a great example because it really helps students understand the concept of dividing something in half. We were able to rewrite the formula in a much more student friendly way.
(length x width) ÷ 2