Math

Math Focus Textbook

Focus 8 math textbook - all solutions

Current Focus SS 8.2- Surface Area of Prisms and Cylinders

This section requires the use of a geometry kit and a calculator.

Grade 8 extends the understanding of 2D objects to their 3D counterparts. For this section, we focus mostly only on area for right prisms (think boxes) and cylinders (think Pringles can). Problems may involve triangular prisms as well. Later, the shift is to volume of the same objects. The goal is to generalize strategies that allow for the calculation of surface area. In other words, last year, students used formulae to solve for polygons and circles. This year, they will apply the same formulas to determine the area of more complex 3D objects that have sides that are a collection of those shapes.

Concepts and terms - application of various formulas for the area of right parallelograms and circles, triangles; edge, vertex, face, prism, cylinder

• (from Gr. 7) A = BH (parallelogram), A = πr2 (circle) A = .5BH (triangle)

• a formula cheat sheet is provided in class