## Tuesday, May 28, 2013

### 4.MD.C.6 Measure Angles Using a Protractor

4.MD.C.6 Measure angles in whole number degrees using a protractor.

Using Microsoft Word, I inserted images into a Word document to create various shapes.

The children had a lot of fun using protractors, sharing answers, and trying to determine the angle measurements.

I like to use these circular protractors, because it is easy for the children to understand that there are 360 degrees in a circle and each little edge mark around the outside edge of the protractor is one degree.

I was also pleased with how successful many of the students were with measuring.

Rigoberto knew that every quadrilateral has 360 degrees. He also knew that all triangles have 180 degrees, so he used this information to divide the arrow polygon into two non-overlapping shapes--a rectangle and a triangle.

Next, Rigoberto proved that the angle measurement inside the arrow shape was 540 degrees. He demonstrated this by adding 360 degrees + 180 degrees.

Very sharp thinking, Rigo!!

After sharing answers with each of the polygons, I told the students to turn their papers over and trace two circles around their protractors.

I told them to put 4 points anywhere on the circle, connect the dots to form a quadrilateral, and measure each of the inside angles.

I was impressed with how well the children were able to measure! Even though Jorge did not know that all quadrilaterals have inside angles that total up to 360 degrees, he still came very close with 359 degrees in his measurements.  Well done, Jorge!!

After sharing answers at their tables, several came up to the overhead to show the class their solutions.

Ediverto was VERY proud of his 55 degree measurement on his quadrilateral and showed it to the class.

Terrific measuring everyone.  :)