Working with a map that does not have a coordinate system on it, small, collaborative teams must come up with a coordinate system for their map. Groups then explain their coordinate structure to the class.

Boat ramps move with waves and changes in water level. Scholars decide on the proper length for a ramp so the angle connecting both sides is appropriate. They visualize the situation and use a simulation to view the results with their...

Four is the perfect number—if you're talking about parallelograms. Scholars determine a possible fourth vertex of a parallelogram in the coordinate plane given the coordinates of three vertices. They read a conversation...

While the lesson focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can they...

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...

Your learners find as many rigid motions of the plane as they can that are symmetries of the configuration of circles. Rigid transformations of the plane are explored and become more concrete to them as they visualize and execute...

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...

When mathematical errors happen, part of the learning is to figure out how it affects the rest of your calculations. The activity has your mathematicians solving for the area of a circular pipe and taking into consideration any errors...

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...

Geometers explore symmetries of isosceles triangles by using rigid transformations of the plane. They complete four tasks, including congruence proofs, which illustrate the relationship between congruence and rigid transformations. The...

Your learners collaboratively find the lines of symmetry in an equilateral triangle using rigid transformations and symmetry. Through congruence proofs they show that they understand congruence in terms of rigid motions as they...

Making money is important to teenagers. It is up to your apprentices to determine how much two wage earners make with their after school jobs. Participants work with a table, an equation, and a graph and compare the two workers to see...

One step at a time! A seemingly linear relationship becomes an entirely new type of function. Young scholars build their understanding of step functions by completing a three-stage activity that incorporates multiple representations of...

Explore how lines of symmetry help define different categories of quadrilaterals. Looking at a square, rectangle, trapezoid, and parallelogram, young mathematicians discover that each shape has its own, unique symmetry. Encourage your...

After learning that the sum of interior angles for triangles is 108 degrees, take it further to show that the sum of angles in any polygon is the same! Using hexagons, pupils practice finding the measure of the six congruent angles. Make...

Learners follow a series of instructions for drawing and coloring different shapes in order to learn the difference between the perimeter and area of a polygon. Then they are asked to find the perimeter and area of a 3x4 rectangular...

Just exactly where does the name conic come from? This brief hands-on exploration explains it all. Have your class cut cones to create their own conics, then assess their understanding with a few identification problems. Consider making...

If both pairs of opposite sides of a quadrilateral are congruent, is the quadrilateral a parallelogram? This task asks learners to determine the answer and to support their answer with a proof. The resource includes a commentary for...

An upper-level treatment of what is often presented as a basic concept (the right angle of an inscribed circle on the diameter), this activity really elevates the mathematical thought of the learner! Expected to develop formulas...

Class members work in pairs to build a catapult to launch a grape a given distance. The catapult project, a compound machine, reinforces pupils' understanding of simple machines.

Students, teachers, and parents alike will enjoy this challenging math site. It contains a clever brain teaser section plus creative problems related to algebra, geometry, measurement, numbers, statistics, and probability. A Spanish...

This site provides a definition for plane figure (at the top of the page) and a few examples.

In this activity, you will explore the invariant properties of rotations and the results of rotations in the coordinate plane.

In this activity, students will explore the properties of rotations and the relationships between the original and image figures.