Students are asked to calculate the areas of polygonal figures. They can use hash marks to create square units and to count the units. Some figures require the counting of half units. This CYBERCHASE activity is motivated by the question of whether or not Hacker belongs in jail for staking a land claim that is larger than that of Judge Trudy's. The CyberSquad helps him prove that the two claims are equal in area.
Part I: Learning Activity
1. Distribute the Handout: "Sensible Flats" . Have students work in pairs to complete the handout.
2. Ask each pair to answer the first two questions and to complete "Prediction One" on the chart.
3. Tell students that they are going to watch a video clip that shows how to measure Judge Trudy's land.
4. Show students the Calculating Rectangular Area QuickTime Video .
5. Ask students to work together to find a way to calculate the area of Hacker's land claim, then compare it to Judge Trudy's. Have them complete "Prediction Two" on the chart.
6. Watch the Comparing Regular and Irregular Areas QuickTime Video .
7. Tell the students that in this clip, Hacker tells the Judge that his land plot is not bigger than hers. She asks him to prove it. As they watch, ask students to pay attention to the way the CyberSquad proves it.
8. Compare the way the CyberSquad proves it with the methods the students used in the introductory activity.
Part II: Assessment
Assessment: Level A (proficiency): The students are asked to find the areas of a set of land claims in which all the polygons are made of grid squares or triangles, then order the polygons from large to small.
Assessment: Level B (above proficiency): The students are asked to find the areas of a set of land claims in which all the polygons have hash marks but no gridlines, then order the polygons from small to large.