Now that using a protractor is a Common Core skill for 4th grade, here is a little freebie to help your students, (and maybe you too, if it has been a while since you've had to use one!)
You get a large version of the poster which can be projected on your interactive white board or printed out poster-sized. There is also a page with a smaller version, which is great to print out for students to glue into their math notebooks.
Please check out my other geometry products, which go into more detail about how to use a protractor not only to measure angles, but to sketch specific angles.
Geometry SMARTBoard and Printables Bundle: Lines and Angles
Geometry SMARTBoard File: Lines and Angles
Geometry Printables: Lines and Angles
Geometry Polygon Resources:
Geometry SMARTBoard and Printables Bundle: Polygons
Geometry SMARTBoard File: Polygons
Geometry Printables: Polygons
Geometry Vocabulary Cards for Polygons