Teaching Math: Identify and Name Angles

Students in upper elementary and middle school math classes learn to identify and name different types of angles. Teaching memory tricks to students and involving them in hands-on activities can help them remember weeks from now what they're learning today.

Name the Angles

Acute Angle < 90°
Right Angle = 90°
Obtuse Angle > 90°, < 180°
Straight Angle = 180°
Reflex Angle > 180°, < 360°

Teach a Riddle

Offer math students a silly sentence that will aid them in remembering the names of the angles, starting with the smallest in size, acute. The first letter of each of the five angle names corresponds to the first letter of each word of this sentence:
A Riddle Often Sounds Ridiculous.

At this point, I usually ask if anyone knows a riddle they'd like to share. Of course, there are always volunteers. After each of about four riddle shares, we all say, "A Riddle Often Sounds Ridiculous." It may sound 'ridiculous' to you...but it works with kids.

Memory Trick

Students always seem to mix up the terms for acute and obtuse angles, since both words are rather foreign to them. I say something like, "You've all seen a cute little baby...well, the acute angle is the baby angle...it's a "cute little angle." I can't tell you how many times the students bring that up throughout the year. Anything that helps them to remember is a good thing.

Hands-On

Next, we 'act out' angles. I ask a student to go to the classroom door and open it into an acute angle. The next student opens the door into a right angle, and so on. The students start to make the connection that the angles they learn about in math class go beyond paper and pencil.

A group of students volunteers to be 'cheerleaders'. They go to the front of the class and demonstrate how cheerleaders might position their arms in a cheer. The discovery is that cheerleaders use angles all the time.

Finally, I choose a student to shout out angle names. All students participate now by opening their math notebooks into the formations of the given angles.

When their hands are active, their brains are more engaged.

Once students have had adequate hands-on practice, they draw and label 3 of each angle type. The lesson culminates with partners comparing drawings as I circulate the classroom to spot check.

When students have fun and become active in the learning process, it's more rewarding for the teacher-and the information has a better chance of staying inside those teenage brains.

Other math articles:
Math Problem Solving: Don't Protect Students from Frustration
Have Fun Teaching Squares and Square Roots
An Interactive Approach to Adding Positive and Negative Numbers