Minnesota Academic Standards
MN.4.3. Geometry & Measurement
4.3.2. Understand angle and area as measurable attributes of real world and mathematical objects. Use various tools to measure angles and areas.
4.3.2.1. Measure angles in geometric figures and real-world objects with a protractor or angle ruler.
4.3.2.2. Compare angles according to size. Classify angles as acute, right and obtuse.