In __yesterday's post __we reviewed how to estimation, representing and unknown quantity, and using a formal input-output table. Today marks the 2/3 point of the review and discusses the first standard in Reporting Category 3 - Geometry and Measurement.

**Area**

Students first learned about area in the 3rd grade by visualizing squares inside a shape. Now they extend the knowledge to solving for area without the use of visual squares. Here's a video to help you master this important skill.

After learning more about area, you're ready to solve this problem from a released STAAR test.

**Note: The test item asked students to measure using a ruler. The **__length __**of the picture is 5 inches and the **__width__** is 3 inches.**

**Perimeter**

Students have learned about perimeter previously in the 3rd grade. Now their knowledge is extended to include formulas as well. Here's a quick video showing what that means.

With this information about counting a collection of bills and coins, try your hand at this sample problem below.

Also, a __related video__ shows how to derive the formulas for perimeter of a square and rectangle.

**Lines of Symmetry**

This important standard only appears in 4th grade. Students must not only learn what symmetry means but carry that knowledge with them moving forward. Here's a short video explanation.

Hopefully that helped clear up the concept. Now you're ready to try the following problem.

**Correct Answers**
Here's the video with the answers and explanations. Make sure you've worked them out yourself first!

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