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...

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...

Two hands-on activities celebrate the sun and moon autumnal equinox. First, scholars create a cairn using a shoebox, flashlight, and drawing tools to view the sun's progression. Second, learners take to the kitchen to bake mooncakes...

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...

So many times the characteristics of triangles are presented as a vocabulary-type of instructional activity, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a...

Bringing together the young artists and the young organizers in your class, this lesson takes that popular topic of tessellations and gives it algebraic roots. After covering a few basic properties and definitions, learners attack the...

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...

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...

This collaborative activity investigates the meaning of a trapezoid and a parallelogram. It begins by presenting two different definitions of a trapezoid. Learners are to reason abstractly the difference between the two definitions and...