Cluster 1: Draw and identify lines and angles, and classify shapes by properties of their lines and angles. (Additional Cluster)Archived

Students are asked to determine if lines drawn on two-dimensional figures are lines of symmetry and to explain their decisions.

Type: Formative Assessment

Students are asked to identify right, acute, and obtuse angles in a two-dimensional figure, and explain the differences among these types of angles.

Type: Formative Assessment

Students are asked to use a line of symmetry to complete a drawing. Additionally, they consider how to describe a line of symmetry.

Type: Formative Assessment

Students are asked to identify parallel and perpendicular sides and explain how they know.

Type: Formative Assessment

Students are asked to identify line-symmetric figures and then draw the lines of symmetry.

Type: Formative Assessment

Students are shown three triangles that fit a rule (each has a right angle) and are asked to determine which of three other triangles also fit the rule.

Type: Formative Assessment

Students are asked to determine how many lines of symmetry a square has by drawing the lines of symmetry. Students then consider whether all quadrilaterals have four lines of symmetry.

Type: Formative Assessment

Students are asked to use shape descriptions to sketch shapes and explain why some cannot be sketched.

Type: Formative Assessment

Students are asked to use shape descriptions to sketch shapes and explain why some cannot be sketched.

Type: Formative Assessment

Students locate points, lines, line segments, and rays in a given diagram.

Type: Formative Assessment

Students are asked to draw parallel lines, perpendicular lines, a point, and a line segment. Students also explain how a line segment is different from a ray or line.

Type: Formative Assessment

In this lesson, you will find clip art and various illustrations of polygons, circles, ellipses, star polygons, and inscribed shapes.

Type: Image/Photograph

This set of geometry challenges focuses on creating a variety of polygons as students problem solve and think as they learn to code using block coding software.  Student will need to use their knowledge of the attributes of polygons and mathematical principals of geometry to accomplish the given challenges. The challenges start out fairly simple and move to more complex situations in which students can explore at their own pace or work as a team. Computer Science standards are seamlessly intertwined with the math standards while providing “Step it up!” and “Jump it up!” opportunities to increase rigor.

Type: Lesson Plan

This is lesson 2 of 3 in the Moon Phase unit. This lesson will help students design a flowchart model to find the phase of the Moon by making decisions based on certain conditions. This lesson also gives students insight into working with the design model made earlier and an opportunity to upload/draw costumes of different lunar phases in Scratch.

Type: Lesson Plan

This is lesson 1 of 3 in the Moon Phase Unit. This lesson introduces students to the eight Moon phases and their names in a counter-clockwise sequential order starting with the New Moon as phase 1. Students will also be introduced to how a flowchart can help make decisions, in this case whether or not the Moon is full.

Type: Lesson Plan

This lesson will provide students with the opportunity to see angles all around them. Students will be able to see how and where geometry exist in the real world.  Please note that this lesson focuses on identifying acute, obtuse, right, straight and reflex angles.

Type: Lesson Plan

In this lesson which focuses primarily on angles, students work in collaborative groups to construct a two-dimensional model of a county fair. 

Type: Lesson Plan

Students will explore the concept of line symmetry in this lesson. Students will explore two-dimensional pictures and decide whether or not each image has symmetry. Students will also fold pre-cut capital letters to decide whether or not each letter has symmetry.

Type: Lesson Plan

In this lesson students will make snowflakes, promoting creativity and self-expression, and use them to identify geometric terms. It also gives them an opportunity to follow a sequenced set of instructions for a given outcome.

Type: Lesson Plan

This is a lesson that introduces right, acute, obtuse, reflex, straight angles in a fun and challenging way.

Type: Lesson Plan

This is a fun, hands-on activity designed to help students identify and measure obtuse, acute, right, straight and reflex angles. Students create a manipulative tool in their math journals to help them gain understanding of this concept.

Type: Lesson Plan

In this lesson, students work to identify points, lines, line segments, rays, angles and perpendicular and parallel lines. Students create webs of yarn and analyze the web for geometric properties listed above. A teacher can select which vocabulary terms are appropriate for the class.

Type: Lesson Plan

Students will use paper cutout and geoboards to find and create lines of symmetry. Students will have the opportunity to work with a partner and independently.

Type: Lesson Plan

Students work together as a class and in small groups to classify quadrilaterals.

Type: Lesson Plan

Students will draw a town based on a set of given directions using the geometry terms (parallel, perpendicular, and intersecting lines). This activity is designed to be taught after the students having learned the meanings of the geometry terms and the ability to identify examples of each.

Type: Lesson Plan

Students will use small paper airplanes to model rotations required to turn onto a runway. Students will rotate planes 45, 90, 180, 270, and 360 degrees. Students will identify and describe the results of rotations using benchmark angles.

Type: Lesson Plan

The student will be engaged in a paper plane making activity while discovering the attributes of different triangles. The students will learned the similarities and differences of the following triangles: scalene, isosceles, equilateral, right, obtuse, and acute.

Type: Lesson Plan

Overcome the nightmare of quadrilateral classification based on the presence of parallel, perpendicular, and congruent sides as you complete this interactive tutorial.

Type: Original Student Tutorial

Help a surfing crab learn how to find parallel and perpendicular sides in a variety of polygons as you complete this interactive tutorial!

Type: Original Student Tutorial

Classify and name angles in two-dimensional shapes to help a robot create a path using angles in this interactive tutorial.

Type: Original Student Tutorial

Help the Symmetry Sisters save the City of Symmetry Line and the State of Arithmetic from the Radical Rat in this interactive tutorial!

Type: Original Student Tutorial

Identify right triangles and explain the properties shared by all right triangles in this interactive tutorial.

Type: Original Student Tutorial

Identify parallel lines and line segments, as well as perpendicular lines and line segments in two-dimensional figures by joining Parallel Man and Perpendicular Man as they help Mayor Mathematics save Mathopolis in this interactive tutorial.

Type: Original Student Tutorial

This activity provides students an opportunity to recognize these distinguishing features of the different types of triangles before the technical language has been introduced. For finding the lines of symmetry, cut-out models of the four triangles would be helpful so that the students can fold them to find the lines.

Type: Problem-Solving Task

This task provides students a chance to experiment with reflections of the plane and their impact on specific types of quadrilaterals. It is both interesting and important that these types of quadrilaterals can be distinguished by their lines of symmetry.

Type: Problem-Solving Task

This is an instructional task that gives students a chance to reason about lines of symmetry and discover that a circle has an an infinite number of lines of symmetry. Even though the concept of an infinite number of lines is fairly abstract, students can understand infinity in an informal way.

Type: Problem-Solving Task

The purpose of this task is for students to measure angles and decide whether the triangles are right or not. Students should already understand concepts of angle measurement  and know how to measure angles using a protractor before working on this task.

Type: Problem-Solving Task

This activity asks students to visualize and generate shapes, paying close attention to the definitions of the polygons. Learners are given a sheet of isometric grid paper and asked to find and sketch 12 specific shapes. A recording sheet is attached where students must justify the shape they generated by using the definitions of the polygons. Ideas for implementation, extension, and support are included along with printable grids and a link to a website with shape definitions. It would be beneficial for students to work with partners in order to construct viable arguments and critique the reasoning of others.

Type: Teaching Idea

The problem challenges and extends students' spatial awareness with 2D shapes. The students are given three different irregular shapes. The goal is to divide each of them into two parts that are exactly the same shape and size.

The Teacher's Notes page offers rationale, suggestions for implementation with a link to Happy Halving (cataloged separately), discussion questions, and ideas for extension and support.

Teachers can print the "printable page" for students. Students could cut out shapes and fold to find the line of symmetry, use grid paper, and/or use geoboards.

Type: Teaching Idea

In this activity, learners use a hand-made protractor to measure angles they find in playground equipment. Learners will observe that angle measurements do not change with distance, because they are distance invariant, or constant. Note: The "Pocket Protractor" activity should be done ahead as a separate activity (see related resource), but a standard protractor can be used as a substitute.

Type: Teaching Idea

This lesson is designed to introduce students to quadrilaterals and the terms and properties associated with quadrilaterals. This lesson provides links to discussions and activities related to quadrilaterals as well as suggested ways to integrate them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one.

Type: Teaching Idea

This Khan Academy tutorial video presents examples and explanations for categorizations of perpendicular sides and right, obtuse, and acute triangles.

Type: Tutorial

In this Khan Academy tutorial video triangles are categorized by angles or side lengths of a specified size.

Type: Tutorial

This Khan Academy tutorial video defines and illustrates parallel and perpendicular lines.

Type: Tutorial

This Khan Academy tutorial video identifies acute, right, and obtuse angles and justifies each identification. 

Type: Tutorial

This video discusses the differences between lines, line segments and rays.

Type: Tutorial

This virtual manipulative allows you to create, color, enlarge, shrink, rotate, reflect, slice, and glue geometric shapes, such as: squares, triangles, rhombi, trapezoids and hexagons.

Type: Virtual Manipulative