DK Publishing
Using a Protractor
Learn how to measure acute, right, and obtuse angles with a protractor. After reviewing the way the protractor works, fourth graders measure nine angles on their own. For extra practice, have them measure different angles in their...
Math Mammoth
Measuring Angles
The first of two pages displays various angles as the measure of degrees of a circular arc. An explanation is written, and learners are asked to model each by holding up two pencils as the rays. The second page provides instruction on...
McGraw Hill
Lines and Angles
Why was the obtuse angle upset? Because it was never right! A valuable resource is loaded with background information on types of angles and lines. Learners review the characteristics of parallel, perpendicular, and intersecting lines,...
Curated OER
Estimating and Measuring Angles (C)
In this estimating and measuring angles worksheet, students examine 6 angles, estimate their measurements, and then measure them using a protractor.
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy Triangle,...
Illustrative Mathematics
Finding an Unknown Angle
Teach your class how to apply their knowledge of geometry as they explore the unknown. In order to find an unknown angle, students must understand that rectangles have four interior right angles, that right angles have 90 degrees, and...
Curated OER
How Do We Measure Angles
In these angles and geometry worksheets, students learn about different kinds of angles, angle measurement, and other geometry facts. Students complete 15 questions.
Noyce Foundation
Time to Get Clean
It's assessment time! Determine your young mathematicians' understanding of elapsed time with this brief, five-question quiz.
Curated OER
Angles Identification
In this assignment, math whizzes identify angles as either being obtuse, acute, right, or straight. Students identify six angles. The publisher states that this is designed with CCSS.Math.Content.MD.6 in mind, but it really does not ask...