The Tangled Angles Game is a great way to get kids to develop an understanding of the different types of angles and to distinguish between acute, obtuse, right, straight, and reflex angles. Sometimes kids have a hard time understanding why a straight angle is even an angle, but the use of the geoboard makes that concept much clearer. You’ll need a fairly large geoboard to ensure that you can follow the instructions that state not to let the arms of the angles cross over each other and not to reuse pegs. If the available geoboards are too small you may want to suspend at least one of those rules to ensure the students will have time and space to try every different type of angle. You might also ask students to not extend the sides of their angles more than three pegs in length to ensure that there will be plenty of space to create other angles.

This is a good time to take the opportunity to explain to students that the arms of an angle are really arrows that continue into space. The geoboard just shows the sides as if they were segments since it’s only a representation of how different angles work in space. If you have several different players playing this game you may want to give them elastic bands in different colors so they can keep track of the angles that belong to them as the angles get tangled.

Another adaptation is to tell students that they must link to the previous player’s angle. After a player creates an angle on the geoboard, the next player has to use one point of that angle in his or her new angle. It will be even trickier to use either the vertex or the end points of the line segment sides to create a new angle instead of placing it anywhere on the geoboard where there’s space.

Common Core Mathematical Standards 4.G Draw and identify lines and angles, and classify shapes by properties of their lines and angles.