Curated OER
Reflecting Reflections
A triangle rests in quadrant two, from which your class members must draw reflections, both over x=2 and x=-2. This focused exercise strengthens students' skills when it comes to reflection on the coordinate plane.
Curated OER
Geometry- Coordinate Plane
Students plot points on a coordinate grid. In this coordinate plane lesson, students use a coordinate grid to locate the perimeter points of pictures, identify quadrants and use the coordinate points to draw the picture on a blank...
Curated OER
Geometry: Helix-a-Graph
High schoolers use geometry to create art. In this geometric graphing and patterns lesson, students create a helix-a-graph by plotting points on a grid that follow a certain pattern and analyze the drawing they created.
Curated OER
Let's Plot Points
Use coordinate grid paper to plot points and identify shapes that are already plotted on the paper by saying their coordinates. Pupils also measure the distance between points and play the game Battleship. There are several web links and...
EngageNY
Segments That Meet at Right Angles
Can segments be considered perpendicular if they don't intersect? Learners look at nonintersecting segments on the coordinate plane and make conclusions about the lines that contain those segments. They determine if they are...
Curated OER
Point Reflection
Use this task as an exit ticket for your eight graders during the geometry unit. All they need to do is identify the coordinates of a point reflected over y=2000.
TED-Ed
Pixar: The Math Behind the Movies
When will we ever use this? A Pixar movie maker explains to students how math is used in the creation of animated films. The movie maker discusses the importance of coordinate planes, transformations and translations, and trigonometry.
Curated OER
Lines in the Coordinate Plane
Students graph lines in a coordinate plane. For this geometry lesson, students graph lines on a coordinate plane, and identify the slope. They classify the lines as parallel or perpendicular and write an equation of a given line.
Illustrative Mathematics
Why Does SSS Work?
While it may seem incredibly obvious to the geometry student that congruent sides make congruent triangles, the proving of this by definition actually takes a bit of work. This exercise steps the class through this kind of proof by...
EngageNY
Rotations of 180 Degrees
What happens when rotating an image 180 degrees? The sixth lesson in the series of 18 takes a look at this question. Learners discover the pattern associated with 180-degree rotations. They then use transparency paper to perform the...
Curated OER
Compound Inequalities and Graphing
Put geometry skills to the test! Learners solve compound inequalities and then graph the inequalities on a coordinate plane using their geometric skills. They identify the slope and y-intercept in order to graph correctly. I like this...
Curated OER
Distance Formula
Learners calculate the distance between two points using the distance formula. In this geometry lesson, students derive the distance formula using the Pythagorean Theorem.
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...
Curated OER
A World of Symmetry
Students identify lines of symmetry. In this symmetry instructional activity, students create objects and identify their lines of symmetry. They answer questions about lines of symmetry. Students cut shapes out of cookie dough and...
Curated OER
Traveling aroud Our Town
Students are asked to describe to a partner how he or she walks to school or the bus stop. They are shown on the overhead an one-inch grid paper, and at the intersection of two lines on the grid paper, students are shown a house and...