A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem. 

Use the alphabet as a tool for teaching your class about geometric figures. Break apart capital letters into line segments and arcs. Classify angles as right, acute, or obtuse. Identify parallel and perpendicular lines. An excellent...

Build a solid foundation on which to develop future concepts. Through a guided exploration, learners compare and contrast the characteristics of points, lines, planes, rays, and segments. They measure lengths and practice notation for...

Who knew quilting would be so mathematical? Introduce linear equations and graphing while working with the lines of pre-designed quilts. Use the parts of the design to calculate the slope of the linear segments. The project...

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...

Keep young mathematicians on point with this coordinate plane activity. From plotting ordered pairs to identifying the quadrant and coordinates of specific points, this resource covers all the basic skills students need to have when...

Connect algebra and geometry on the coordinate plane. The eighth unit in a nine-part integrated course has pupils develop the distance formula from the Pythagorean Theorem. Scholars prove geometric theorems using coordinates...

Geometry is more than just vocabulary. Pupils learn the basic geometric definitions and how to identify and name points, lines, and planes. Though the first lesson is packed with related vocabulary, scholars experience four postulates...

Scholars determine distances on the coordinate plane to find areas. The instructional activity begins with a proof of the formula for the area of a parallelogram using the coordinate plane. Pupils use the coordinate plane to determine...

Programming a robot is a mathematical task! The activity asks learners to examine the process of programming a robot to vacuum a room. They use a coordinate plane to model the room, write equations to represent movement, determine the...

Good things happen when algebra and geometry get together! Continue the exploration of coordinate geometry in the third lesson in the series. Pupils explore linear equations and describe the points of intersection with a given polygon as...

How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...

Connect the dots to graph a linear function. Young mathematicians use an interactive to first plot provided points on a coordinate plane. They connect these points with a line and then answer questions about the slope and y-intercept of...

It seems perpendicular lines have slopes which follow a specific rule. Scholars use an interactive to investigate this rule by moving a pair of lines on a coordinate plane. They find that perpendicular lines have slopes that are opposite...

See how vertical and horizontal lines have special equations. Scholars drag vertical and horizontal lines onto a coordinate plane to graph given equations. They then answer a set of challenge questions on the topic.  

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.

Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...

We can mathematically model the path of a robot. Learners use parametric equations to find the location of a robot at a given time. They compare the paths of multiple robots looking for parallel and perpendicular relationships and...

What, you mean there is algebra in a Geometry class? Pupils review graphing and writing the equations of lines in slope-intercept form. The instruction follows the "I do, we do, you do" framework of a lesson. The instructor first...

One of the hardest skills for many young geometers to grasp is to move beyond just declaring obvious things true, and really returning to fundamental principles for proof. This brief exercise stretches those proving muscles as the...

You know about the tangent function, but what are tangent lines to a circle? Learners investigate properties of tangents through constructions. They determine that tangents are perpendicular to the radius at the point of tangency,...

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. 

Challenge your class to use straight lines when estimating the length of a curve. An engaging interactive allows individuals to place line segments one after another along the arc. Learners determine that the more lines used, the better...

Designs from lines are sublime. Scholars create colorful designs by connecting points on an interactive coordinate plane. They answer questions about slope and quadrants based on their designs.