An introduction to triangles. Read all of the questions first, and do not move any off the triangles until instructed to do so. The teacher is here for guidance, but this should be an independent or group observation. Write down what you observe and share it with the class.

- Make a prediction about the relationship between the quadrilaterals and triangles of the same color
- Find the area of quadrilaterals A, B, C, and D using what you learned yesterday.
- Estimate the Area of the triangles A_1, B_1, C_1, and D_1 using the grid.
- Move the triangles around. Try placing them on top of the quadrilaterals.
- What can you say about the quadrilaterals and triangles of the same color?
- Write down everything you observe. What do you notice? What do you wonder?
- Can you think of a way to calculate the area of the triangles?
- Will this work for all triangles?
- What do you need to know about a triangle to find this formula?