Geometry is typically the one topic in math I run out of time to teach thoroughly. While I certainly believe it’s an important topic, I do place my greatest emphasis on my standards that incorporate number sense and operations. With that shortened time frame, I have to make sure my lessons are as powerful as possible. This post will share a few methods I use for teaching geometry, whether you’re on a time crunch or not! All of the lessons are from my 4th Grade Geometry Unit.
I’ve found that it is a tremendous help to preteach geometry vocabulary before I begin my geometry unit. Geometry is probably my most vocabulary heavy math unit for the year. Fortunately, students are typically familiar with at least some of the terms before beginning the unit. I don’t like to spend too much instructional time with direct vocabulary instruction, so I add geometry vocabulary to our math centers before I begin the unit. I have students go to Study Jams on their Chromebooks and use the content to complete a Geometry Vocabulary Booklet.
After students complete the geometry vocabulary booklet, I recognize that students still won’t have a deep understanding of the terms. However at that point, I’m happy if they have a basic understanding or familiarity with the words. This allows me to focus more on application and problem solving in my math lessons. I do weave in a few vocabulary games to help students remember the terms. Some of my favorites are Geometry: I Have Who Has and Quizlet Live. If you aren’t familiar with Quizlet, I highly recommend it. I’ve written a blog post on how I use it here.
Since at the beginning of the unit students are still learning essential vocabulary, I start by teaching symmetry, which is typically the easiest part of the geometry unit for students. I have students use either pattern blocks or magnatiles to create symmetrical figures. After giving students hands-on opportunities, I have students create a Symmetry Monster using dotted paper.
After I teach symmetry, I introduce types of angles. Students are usually familiar with acute, obtuse, and right angles, so I don’t spend too much time on this, since I teach measuring angles within my measurement unit. However, students do need to be able to identify types of angles to be able to classify shapes. I have found that students have much more difficulty when the angles are within polygons, rather than an isolate angle. I like to have students sort shapes by the types of angles found within the shape.
After teaching angles, I begin teaching types of lines. I focus on lines, line segments, rays, parallel, and perpendicular lines. I have students play a game called I Spy a Line. Students play this game with a partner. They take turns looking for different types of lines (perpendicular and parallel). When students find a set of lines, they highlight the lines. Students should use one color for perpendicular lines and one color for parallel lines. Once students have highlighted a line, they cannot highlight that line again. Students should see how many of each type of line they can highlight.
I love finding ways to incorporate art and math, so we also do a little line art activity. These look particularly nice mounted on black construction paper.
When students are ready to move on from types of lines, I teach different types of triangles. I love using Angle Legs to teach types of triangles. They are a great way to give students hands-on experience with building different types of triangles.
Once students have experienced hands-on opportunities, we use geoboards to problem solve. I like using this Types of Triangles lesson that has students explain concepts about triangles. For example, “Is it possible to make a three sided polygon that is not a triangle?”
I like following up these lessons with triangle practice that allows students to practice identifying triangles and types of angles.
Once I’ve taught symmetry, angles, and lines, I begin going in-depth on types of polygons. I always begin with reading Grandfather Tang’s Journey, and I have students experiment building different shapes with tangrams. I encourage students to embrace the struggle in this activity, because even after teaching this lesson many years, I still can’t build all of the shapes. The purpose of the lesson is in the process and the exploration, not an end result.
Students then sort shapes based on the length of the sides or the type of angles found within the shape. In this lesson, students determine the categories of each of the venn-diagrams. This allows the task to be open ended where students may each have different answers.
I also teach students about irregular polygons, which greatly helps students to apply the rules of polygons in unique ways. They are no longer able to simply memorize what a typical rectangle looks like. Instead, students must apply what they know to design shapes that do not follow traditional norms.
One of my favorite activities for teaching geometry is my Geometry Stations Booklet. In this activity, there are nine different activities for students to complete. Half of the activities are hands-on, and all of the activities are FUN for students!
In my geometry unit, I’ve also included a few games that can be added to math centers. For example, in Spin a Shape, students use the spinner to spin a shape. They cross out a shape that matches the shape the student landed on. Students take turns spinning until all of the shapes are crossed out.
As a culminating task, I’ve created a Geometry Park activity, which is my favorite activity in the pack for teaching geometry. In this activity, students use the Geometry Park Guide to design a community park.
You can find all of the printables and lessons (and many more) in my 4th Grade Geometry Unit.