Worksheet
Curated OER

Lengths, Areas and Shapes - Week 9

For Students 12th - Higher Ed
In this lengths, areas and shapes worksheet, learners explore overlapping and non-overlapping patterns. They identify the number of objects in a pattern, determine how the pattern may be folded to create additional patterns, and...
Lesson Plan
Curated OER

Geometry, Measurement & Reasoning

For Teachers 7th - 9th
Pupils complete worksheets involving rotational symmetry. In this geometry lesson, students complete worksheets to identify rotational symmetry and rotations. They compare and contrast rotated figures. Pupils examine the relationship...
Lesson Plan
Curated OER

Isosceles Triangles

For Teachers 9th - 10th
Students identify the properties of an isosceles triangle. In this geometry instructional activity, students find the midpoint, median and angle bisector of a triangle. They construct angle bisectors and measure missing angles.
Lesson Plan
Curated OER

Triangle Attributes and Measures

For Teachers 7th
Seventh graders explore the concept of triangles. In this triangles activity, 7th graders sort triangles according to various attributes such as acute, obtuse, isosceles, or equilateral. Students find the area and perimeter of triangles.
Lesson Plan
Curated OER

Terrific Tessellations

For Teachers 4th - 6th
Students explore tessellations that are found in nature and everyday objects. They observe the works of M.C. Escher. Students create their own tessellations using pencil and paper.
Handout
Math Open Reference

Math Open Reference: Congruent Line Segments

For Students 9th - 10th Standards
Learn about congruent line segments with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Handout
Varsity Tutors

Varsity Tutors: Hotmath: Congruent Line Segments

For Students 9th - 10th Standards
Find a quick, concise explanation of Congruent Line Segments. Several examples are given and clearly explained.
Activity
Texas Instruments

Texas Instruments: Finding the Shortest Path

For Teachers 9th - 10th
Students discover the shortest distance light travels from an object to the human eye, as the light from the object reflects off a single mirror. In the process they learn about reflection in a line, congruent angles, angle bisectors,...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Congruent Segments

For Teachers 8th Standards
Eighth graders are shown two line segments that are the same length and must describe a sequence of reflections that exhibits a congruence between them. Aligns with 8.G.A.2.
Interactive
Math Open Reference

Math Open Reference: Congruence

For Students 9th - 10th Standards
A complete reference guide to congruence including congruent triangles and polygons. It provides definitions, animation, and interactive activities that enhance further explanation.
Activity
Oswego City School District

Regents Exam Prep Center: Copy a Line Segment and an Angle

For Students 3rd - 8th Standards
This site provides a step-by-step method to construct congruent segments and angles with a straight edge and compass.
Activity
Texas Instruments

Texas Instruments: Perpendicular Bisector of a Line Segment

For Teachers 9th - 10th Standards
Students learn to draw a segment and its perpendicular bisector. They understand right angles and congruent segments. Students observe that changing the length or orientation of the segment changes the perpendicular bisector.
Handout
Math Open Reference

Math Open Reference: Congruent

For Students 9th - 10th Standards
Learn about congruent with this handy reference guide. Provides a detailed definition and examples that enhance further explanation. Includes links to related topics.
Handout
CK-12 Foundation

Ck 12: Geometry: Segments Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This study guide reviews how to measure the distance between two points and the Ruler Postulate. It also introduces congruency/congruent segments and midpoint.
eBook
Mathigon

Mathigon: Geometry: Euclidean Geometry: Definitions

For Students 9th - 10th Standards
This lesson focuses on Euclidean Geometry terminology; such as line, point, line segment, congruence, circle, radius, ray, and more. It defines each term and provides an example of each.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Gpe, G Srt Finding Triangle Coordinates

For Teachers 9th - 10th Standards
Given a picture of a triangle on a coordinate grid, students are asked to find the coordinates of points which divide line segments in a given ratio. Aligns with G-GPE.B.6 and G-SRT.B.5.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Gpe, G Co, G Srt Unit Squares and Triangles

For Teachers 9th - 10th Standards
In this task, learners are shown three unit squares and two line segments connecting two pairs of vertices. They are asked to find the area of a triangle formed by intersecting lines. They can solve it using coordinate geometry or...
Handout
Oswego City School District

Regents Exam Prep Center: Geometry Vocabulary Resources

For Students 9th - 10th
A list of geometry definitions and a matching activity.
Activity
National Council of Teachers of Mathematics

Nctm: Illuminations: Diagonals to Quadrilaterals I

For Students 9th - 10th
This resource explores the diagonals of quadrilaterals. The interactive tool allows learners to examine intersecting line segments in a variety of ways. Topics discussed are perpendicular diagonals, congruent diagonals, and bisected...
Unit Plan
CK-12 Foundation

Ck 12: Algebra: Distance Formula

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept introduces the distance formula and uses it to prove that line segments are congruent. Students examine guided notes, review guided practice, watch...
PPT
Sophia Learning

Sophia: Two Lines Tangent to a Circle: Lesson 3

For Students 9th - 10th
This lesson will present how if two segments from the same point outside a circle are tangent to a circle, then they are congruent. It is 3 of 5 in the series titled "Two Lines Tangent to a Circle."
Activity
National Institute of Educational Technologies and Teacher Training (Spain)

Ministerio De Educacion: Flecha

For Students 1st - 8th Standards
Can you make the second arrow the same size as the first? You will be surprised.
Handout
Purple Math

Purplemath: Conventions

For Students 9th - 10th Standards
A "convention" is "just the way a thing is done!". This reference material lists some common conventions (notational assumptions) for geometry and trigonometry.