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...

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. 

Designers in Prague are not diagonally challenged. The mini-assessment provides a complex pattern made from blocks. Individuals use the pattern to find the area and perimeter of the design. To find the perimeter, they use the Pythagorean...

Here is a straightforward example of how to apply the Pythagorean Theorem to find an unknown side-length of a trapezoid. Commentary gives additional information on proving that the inside of the trapezoid is a rectangle, but is...

What figure is formed by connecting the midpoints of the sides of a quadrilateral? The geometry assessment task has class members work through the process of determining the figure inscribed in a quadrilateral. Pupils use geometric...

Out with the old and in with the new. Learners use a set of prices of computer monitors from 1994 to make a prediction. They then use one current price and what they know about the old prices to make a more recent prediction. Their...