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...

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...

Your Geometry learners will collaboratively prove that the tangent line of a circle is perpendicular to the radius of the circle. A deliberately sparse introduction allows for a variety of approaches to find a solution. 

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...

This one activity requires young geometers to pull together information they are currently learning with things they have learned previously. Here they rely on understanding something about parallel lines, alternative interior angles,...

High School geometers verify through experimentation certain properties about dilations. This multi-step problem challenges them to construct examples of dilations to verify specific facts, the final step provides an opportunity to more...

Bank on geometry to line up the shot. The resource asks the class to determine the location to bank a cue ball in a game of billiards. Using their knowledge, class members determine where to hit the bumper to make a shot and discuss...

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...

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...

Given a pair of parallel lines and a triangle in between, geometers prove that the sum of the interior angles is 180 degrees. This quick quest can be used as a pop quiz or exit ticket for your geometry class.

Without ever using the actual term, this exercise has the learner develop the key properties of the midsegment of a triangle. This task leads the class to discover a proof of similar triangles using the properties of parallel...

Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...

Wrap up the unit in one final design. Pairs use their knowledge of aviation to design new flying machines and record how their designs take into consideration the forces that act upon airplanes. The pupils determine whether their designs...

Geometry meets earth science as high schoolers investigate the cause and features of the four seasons. The effects of Earth's axis tilt features prominently, along with both the rotation of the earth about the axis and its orbit...

Young mathematicians investigate the use of symmetry in graphic design. After first learning about reflection, translational, and rotational symmetry, children use this new knowledge to identify symmetry in letters of the...

Need an activity for teaching the Pythagorean Theorem? Geometry juniors apply the Pythagorean theorem to two triangles to determine a final calculation. 

Looking for a fun and creative way to celebrate Pi Day? Then this is the resource for you. From a scavenger hunt and trivia contest to PowerPoint presentations and skills practice worksheets, this collection of materials is a...

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. 

A deceptively simple question setup leads to a number of attack methods and a surprisingly sophisticated solution set in this open-ended problem. Young geometers of different strengths can go about defining the solutions graphically,...

Your learners find and construct the line of reflection between a triangle's pre-image and its reflection image in this short activity.

Your geometry learners explore Angle-Side-Angle congruence in this collaborative task. The sum of the interior angles of all triangles being one hundred eighty degrees, is the key learners will discover as they explain their reasoning...

Learners investigate the symmetries of a convex quadrilateral in a collaborative activity. Rigid motion and complements are explored as learners analyze different cases of reflections across a line.

The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...

It's amazing the complex figures that can be made using only a few simple shapes. Following a class reading of the children's book Grandfather Tang's Story by Ann Tompert, young mathematicians use sets of tangrams to create models...