TANGRAMS, COMPOSITE FIGURES, & AREA OH MY!

Each student was given a set of Tangrams. They were instructed to

1. Choose 4 of the pieces and create a figure. 
2. Trace the figure on page 66 of their math notebook.
3. Examine the figure and tell how they could calculate the area of their shape. (Most students were very perplexed. However after some discussion they began to realize they had the proper tools necessary to actually do this.)
4. Trace each individual shape within their figure. (At this point most students began to realize they could find the area of each piece and then total up the area)
5. Number each piece in the figure.

I then gave the students the base and height measurements for each shape.

• small triangle - b=3cm   h=2cm
• medium triangle - b=5cm  h=4cm
• large triangle - b=8cm  h=8cm
• parallelogram - b=3cm  h=2cm
• square - b=3  h=3

Students were then asked to calculate the area of each piece they used in their figure. Next they added up the total area of all pieces to get the area of their composite figure. Below is an example from a student math notebook.

In conclusion students learned they are able to "Break up" the figure to make squares and triangles. These are the only 2 formulas they are using currently to find the area.