Teachers, including myself are always wondering why students are confused between area, perimeter, surface area and volume. The class can't move on when more than half of the students can't memorize the area formula for basic shapes like squares, rectangles, and triangles. In most cases, the classroom values too much on the formulas that we forget about the key concept in Geometry.
Let's compare the following two examples to help us understand why students are struggling with calculating area. Which assignment is more meaningful for the students?
Assignment #1
Assignment #2
Use the following graph paper to draw at least 5 rectangles with an area EXACTLY 24 unit squares. How many 24 unit square rectangle can you draw?
Sample solutions:
- 3 x 8
- 4 x 6
- 2 x 12
- 1 x 24
- 0.5 x 48 (Great discussion for non-whole dimensions)
As a math teacher, I believe that one of the most powerful tool in a math classroom is graph paper. When using graph paper, students can clearly see the dimensions and unit squares in their shapes. Students can simply count the squares if they don't remember the formula. Even for shapes that have partial squares, students can estimate or combine partial squares to make one unit squares.
I am simply sharing my thoughts and experience as a math teacher. I am willing to learn and adapt in order to become a better educator.
Mr. Cudavenguyen
