Instructional Video11:40
2
2
Flipped Math

Properties of Parallel Lines

For Students 9th - 12th Standards
Work within a parallel universe. Scholars learn about the relationships of angles when two parallel lines are intersected by a transversal. They see how to find the measurements of all eight angles by knowing the measure of one angle....
Lesson Plan
EngageNY

Angles Associated with Parallel Lines

For Students 8th Standards
Explore angle relationships created by parallel lines and transversals. The 13th lesson plan of 18 prompts scholars use transparency paper to discover angle relationships related to transversals. Learners find out that these angles pairs...
Interactive1:29
Scholastic

Study Jams! Types of Lines

For Students 4th - 9th Standards
Get jamming with lines and sing along to this karaoke that reviews the main types of lines. Your learners can't forget the main properties of lines when they sing the chorus on the karaoke song after the included slide show. The slides...
Instructional Video9:36
2
2
Flipped Math

Proving Lines Parallel

For Students 9th - 12th Standards
Show it can all be proved. Scholars learn the converses of the properties of parallel lines. Using the converses, pupils determine which lines are parallel based on angle measurements and practice using a flow proof to show that two...
Lesson Plan
Mathematics Assessment Project

Classifying Equations of Parallel and Perpendicular Lines

For Teachers 9th - 12th Standards
Parallel parking might be difficult, but finding parallel lines is fairly simple. In this lesson, learners first complete an assessment task involving parallel and perpendicular lines in the coordinate plane. Individuals then take part...
Worksheet
Curated OER

Parallel and Perpendicular Lines

For Students 9th - 11th Standards
Young geometers get some solid skills practice in evaluating slopes. Beginning with the basics of slope through two points and progressing through properties of parallel and perpendicular lines, the building of skills is gradual and...
Lesson Plan
EngageNY

Informal Proofs of Properties of Dilations

For Teachers 8th Standards
Challenge the class to prove that the dilation properties always hold. The lesson develops an informal proof of the properties of dilations through a discussion. Two of the proofs are verified with each class member performing the...
Assessment
Inside Mathematics

Quadrilaterals

For Teachers 9th - 12th Standards
What figure is formed by connecting the midpoints of the sides of a quadrilateral? The geometry assessment task has class members work through the process of determining the figure inscribed in a quadrilateral. Pupils use geometric...
Assessment
Curated OER

Expressing Geometric Properties with Equations

For Students 9th - 11th Standards
Algebra and geometry are not interchangeable. Demonstrate why not with a series of problems that deal with the equations of circles and equations of lines that meet specific criteria. 
Unit Plan
1
1
Mathematics Vision Project

Similarity and Right Triangle Trigonometry

For Teachers 10th - 12th Standards
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
Lesson Plan
EngageNY

Definition of Reflection and Basic Properties

For Students 8th Standards
Discover the results of reflecting an image. Learners use transparency paper to manipulate an image using a reflection in this fourth lesson plan of 18. They finish by reflecting various images across both vertical and horizontal lines.
Lesson Plan
EngageNY

Special Lines in Triangles (part 1)

For Students 9th - 10th Standards
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
Unit Plan
Mathematics Vision Project

Transformations and Symmetry

For Teachers 9th - 10th Standards
Flip, turn, and slide about the coordinate plane. Pupils define the rigid motions and experiment with them before determining the relationships of the slopes of parallel and perpendicular lines. The sixth unit in a nine-part series...
Activity
1
1
Illustrative Mathematics

A Midpoint Miracle

For Teachers 9th - 12th Standards
Young geometers develop one of the fundamental properties of quadrilaterals (connecting side midpoints gives a parallelogram) in this short but thought-provoking exercise. Using a combination of hands-on techniques and abstract algebraic...
Lesson Plan
EngageNY

How Do Dilations Map Angles?

For Students 9th - 10th Standards
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure. 
Unit Plan
1
1
Mathematics Vision Project

Module 7: Connecting Algebra and Geometry

For Teachers 8th - 10th Standards
The coordinate plane links key geometry and algebra concepts in this approachable but rigorous unit. The class starts by developing the distance formula from the Pythagorean Theorem, then moves to applications of slope. Activities...
Worksheet
Mt. San Antonio Collage

Properties of a Parallelogram

For Students 9th - 12th Standards
More than just a activity, the resource provides a thorough guide to navigate through the land of parallelograms. Filled with definitions and theorems, the resource supports learners through problems such as proofs and finding missing...
Lesson Plan
EngageNY

Fundamental Theorem of Similarity (FTS)

For Teachers 8th Standards
How do dilated line segments relate? Lead the class in an activity to determine the relationship between line segments and their dilated images. In the fourth section in a unit of 16, pupils discover the dilated line...
Lesson Plan
EngageNY

Special Lines in Triangles (part 2)

For Teachers 9th - 10th Standards
Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...
Instructional Video16:33
2
2
Flipped Math

More with Proofs

For Students 9th - 12th Standards
Proofs may be as easy as 1, 2, 3 ... maybe. Pupils participate in creating four example proofs. The presentation uses a list of geometric properties to develop the proofs by filling in both the statements and reasons. Scholars practice...
Lesson Plan
1
1
Illustrative Mathematics

Right Triangles Inscribed in Circles II

For Teachers 9th - 10th Standards
So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Lesson Plan
1
1
Illustrative Mathematics

What Shape Am I?

For Teachers 3rd - 5th Standards
Sharpen your pencil and grab a ruler, it's time to draw some quadrilaterals! Given the definition of a parallelogram, rectangle, and rhombus, learners draw examples and nonexamples of each figure. The three definitions are...
Assessment
Los Angeles County Office of Education

California State Standards: Algebra I

For Students 8th - 10th Standards
Starting a year of Algebra I? This mighty packet practices all of the major topics with different ranges of difficulty. Standards include everything from linear to quadratic to rational expressions. Use it in a...
Worksheet
Mt. San Antonio Collage

Postulates, Angles, and Their Relationships

For Students 8th - 11th Standards
More than a worksheet, learners go through geometry topics example by example on the nicely organized handout. From postulates to classifying angles, there are rules and examples provided for each topic. The ten pages of problems...