Curated OER
Transformational Geometry Using the Geometer's Sketchpad
Young scholars complete a webquest on the various types of symmetry. Using a computer, they explore the concepts of transformational geometry and identify points, segments, lines and planes. They experiment with the rotation of a...
Curated OER
Group Isomorphisms
Students identify and apply properties of triangles. In this geometry lesson, students define equilateral triangles by sides and angles. They build cardboard triangles as they study properties of triangles.
EngageNY
Review of the Assumptions (part 2)
Is the amount of information getting overwhelming for your geometry classes? Use this strategy as a way to organize information. The resource provides a handout of information studied in relation to triangle congruence. It includes a...
EngageNY
Tangent Segments
What's so special about tangents? Learners first explore how if a circle is tangent to both rays of an angle, then its center is on the angle bisector. They then complete a set of exercises designed to explore further properties and...
EngageNY
Transformations—The Next Level
Transform your geometry instruction by incorporating role play into math class. Pupils begin by completing an assessment to locate unknown angles, and then performing a simulation activity to better understand rotations, reflections, and...
Illustrative Mathematics
Similar Triangles
Proving triangles are similar is often an exercise in applying one of the many theorems young geometers memorize, like the AA similarity criteria. But proving that the criteria themselves are valid from basic principles is a great...
Mt. San Antonio Collage
Circles
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated instructional activity provides guided practice through many topics such as central angles, inscribed...
Curated OER
Challenge: Skills and Applications Lesson 3.3
For this angle measures worksheet, learners solve 9 short answer problems. Students find values for x and y given two parallel lines cut by a transversal. Learners use alternate interior, supplementary, and exterior angles to find x and y.
Curated OER
Congruent Triangles
Tenth graders explore congruent triangles. For this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles are congruent by SSS, ASA, AAS, or SAS.
Curated OER
Why can't We Use SSA to Prove Triangles Congruent?
Students investigate triangles and congruences. In this geometry lesson, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.
Curated OER
Geometric Proof and Angles
In this geometry worksheet, 10th graders write two-column and paragraph proofs to prove angle pair relationships. The one page worksheet contains five problems. Answers are not included.
Curated OER
Vertical Angles
In this geometry worksheet, 10th graders investigate vertical angles, solve for vertical angles using equations that are equal and relate it to solving linear equation. There are 10 problems on this worksheet.
Curated OER
Triangles
In this triangles worksheet, 10th graders solve 3 extensive informal geometry problems that involve triangles. First, they sketch a triangle, selecting 3 of the sides and constructing 3 midpoints. Students then draw each of 3 medians by...
Curated OER
Sled Kite Proportions
Students build sled kites. in this kite building lesson plan, students must read directions for kite building and enlarge the proportions of the given kite pattern. Students focus on the angles and line of symmetry in their kite.
Curated OER
Geometry Assessment-"Chapter 2"
In this geometry worksheet, students match terms with definitions, and complete short answer questions about polygons and congruency.
Curated OER
Transformations
Middle schoolers solve and identify 10 different problems that include transformations and identifying translations. They determine if each figure is an example of a translation and explain how each figure may or may not be a...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
Curated OER
Inscribing a Square in a Circle
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
Curated OER
Unit Squares and Triangles
This is an interesting geometry problem. Given the figure, find the area of a triangle that is created by the intersecting lines. The solution requires one to use what he/she knows about coordinate geometry, as well as triangle and angle...
Curated OER
CSI Investigation of Congruence and Similarity
Students differentiate between similarity and congruence using polygons. In this geometry lesson, students label triangles based on their properties. They find missing sides and angles using the interior sum theorem.
Curated OER
Geometry Problem Set I
Students prove angles congruent by use of vertical angles definition, subtraction postulate, and transitivity postulate.
Curated OER
An Introductions to Congruent Polygons
Students differentiate between similar and congruent polygons. In this geometry lesson, students define the theorems and reasons for polygons similarity and congruence. They are given pictures and patterns to differentiate and identify.
Curated OER
Analyzing Body Angles
Students investigate angles of polygons. In this geometry lesson, students identify the relationship between angles and the number of sides in a polygon. They differentiate between sumilarity anf congruence in angles and sides.
Curated OER
Measuring Body Angles
Young scholars use technology to graph and compare angles. In this geometry lesson, students range of motion in the environment. They identify the missing parts of polygons using similarity and congruence.