Solving Environmental Problems through Engineering

Rationale:

The urban area has become dominant in today’s landscape. “In 2009, the number of people living in urban areas (3.42 billion) surpassed the number living in rural areas (3.41 billion), and since then the world has become more urban than rural.³ This is the first time that the majority of the world's population lived in a city”.² As cities grow in size their impact on the environment has become a major issue. Urban development affects the landscape. Open plains and fields of grass and soil are covered with impervious surfaces such as pavement, buildings and asphalt. This change in landscape impacts the environment through water runoff in which storm water is directed away from the soil and its role in replenishing the local water table. Understanding urban runoff requires a strong knowledge of geometry. Generally, area is taught with surface area and volume. Students connect their understanding from area to surface area to volume, scaffolding from two dimensional measurement of flat surfaces (the area of the classroom floor) to three dimensional measurement (surface area and volume of a box of cereal). In this unit, students will calculate the surface area of the space encompassing their school surroundings. Students will distinguish between different types of surfaces found within this vicinity: grass, gravel, concrete asphalt. Students will categorize between by measuring the surface area of the surrounding ground, students will determine the area of a two-dimensional space and not a geometrical solid encompassing the total area of faces. Students will compare differences of surfaces (permeable and impermeable) to distinguish between them. This unit will focus on permeable and impermeable surfaces of area and its role in surface storm runoff and flooding, the measuring of these surface areas using formulas for area, the proportion and rates of absorption and water runoff on both pervious and impervious surfaces. The activities of the unit will be related to the learning standards involving proportions and rates as well as measurement. One of the greatest successes of my previous unit was my student’s investment in the activities involving area, surface area and volume.