In this episode, perimeter is defined and methods of computing the perimeter are discussed. The formula for the area of a triangle is explained, as well as the circumference (or perimeter of the circle) and circle area. Students will also learn to compute the perimeter of a figure given the length of its sides and to classify a three-dimensional shape as a cube, prism, cylinder, pyramid or cone. Grades 3-7. 30 minutes on DVD .