PULSE: Earth Science Section

The lessons are organized to concentrate on important big ideas, which are addressed by a learning cycle approach. At the completion of each big idea’s learning cycle students should be able to answer the corresponding driving question.

Typically, each learning cycle contains four lessons. The lessons associated with a specific learning cycle may take from a couple of days to a few weeks to complete. The first lesson engages the students' interest in the big idea, prompting them to demonstrate the background they bring to the topic and to ask questions. In the second lesson, students explore the big idea, searching for answers to their questions and expanding their understanding of the concept. The third lesson is an opportunity for students to explain the big idea. In the fourth lesson the students apply what they learned to a new situation.

The chemistry learning cycles of "Cultures and Cycles: Arsenic and Human Health" and "From Global to City Air: Air Quality, City Design and Disease", address National Education Standards for earth sciences and students explore how the concepts of earth sciences and world geography are connecected. These two units also address geography.

In "Cultures and Cycles: Arsenic and Human Health", described below, students investigate arsenic exposure via drinking water which is thought to affect thousands every year. But how does arsenic get into the drinking water? How can we get it out of the water and what illnesses does it cause? The answers to these questions help people better understand how arsenic affects their health.
In "From Global to City Air: Air Quality, City Design and Disease", described below, students explore the air impacts on human health and in turn how the humans affect air quality. The relationship between air quality and human health is pointedly clear in this unit as students explore the built community, buildings, highways, and industrial parks, plus environmental and human health.

At the end of the unit, the students will be able to apply their new scientific understanding to the Major Project where they produce a product to demonstrate what they learned in the unit.

For "Cultures and Cycles: Arsenic and Human Health", The major project is to organize and deliver a presentation to an assigned community where there is a large amount of arsenic present in the drinking water. Students will formulate a persuasive advisory to the public educating the community not only about why arsenic is in the water and its’ affects in the ground water, but also the actions that might be taken to reduce the arsenic in the water they consume.
For "From Global to City Air: Air Quality, City Design and Disease", Students take on the role of city planners as they design a city with health at the top of their considerations. Using the actual physical geographical location of major cities, they develop a scaled model of a city including the zones within a city. Students focus on excellent air quality as a feature of a healthy city and using their understanding of climate, weather, and air movement, design their city accordingly.

"Cultures and Cycles: Arsenic and Human Health" 8 Essential Questions for 8 Big Ideas Project time to complete: 8 weeks

1	Essential Question	How do the earth’s geochemical cycles impact the health of the people as regards arsenic poisoning?
1	Big Idea	The earth’s geochemical cycles have a direct effect on the environment that we live in. Sometimes this can be deleterious. For example, arsenic is concentrated by hydrothermal systems resulting in higher concentrations in certain areas which in turn can mean higher concentrations in the drinking water which can have an adverse effect on health. Being part of the bedrock means that arsenic knows no country boundaries in its impact.

2	Essential Question	How do we know the Earth has changed over time?
2	Big Idea	Geologists, like Alfred Wegener, have used evidence from a variety of sources to describe what and how the earth’s plates move.

3	Essential Question	What internal forces are responsible for shaping the Earth’s surface?
3	Big Idea	Geochemical cycles, like mantle convection, drive plate tectonics which in turn is responsible for the formation of many surface features like volcanoes and mountains.

4	Essential Question	Why are there so many mountains and volcanoes away from plate boundaries?
4	Big Idea	Although mountain and volcano formation appear straightforward, there are a variety of ways and places volcanoes and mountains may form.

5	Essential Question	How was the internal structure of the Earth discovered?Deductive reasoning, and indirect observation allowed scientists to discover the composition of the Earth’s interior.
5	Big Idea	Although mountain and volcano formation appear straightforward, there are a variety of ways and places volcanoes and mountains may form.

6	Essential Question	How does Arsenic become concentrated in certain parts of the world?
6	Big Idea	Minerals are not distributed evenly throughout the bedrock. Through geochemical processes, ex. hydrothermal systems, minerals can be concentrated in specific area. Understanding magma intrusions and hydrothermal systems gives students insight into the dynamic nature of earth and geochemical cycles.

7	Essential Question	What external forces have helped shape the Earth’s surface?
7	Big Idea	Weathering is one of many external forces that have shaped the physical features of the Earth. Weathering can change the chemical composition of regions accounts and can account for the accumulation of certain minerals in specific locations.

8	Essential Question	Why is there such variety among the rocks on the Earth’s surface?
8	Big Idea	The three types of rocks are cycled through specific geochemical processes that change them from one type to another.

"From Global to City Air: Air Quality, City Design and Disease" 5 Essential Questions for 5 Big Ideas Project time to complete: 8 weeks

1	Essential Question	How do global weather patterns affect pollution?
1	Big Idea	Water and air pollution are transported from place to place via global air and water patterns.

2	Essential Question	What causes the patterns of air motion on a global scale?
2	Big Idea	Solar radiation heats the Earth unevenly causing changes in air pressure which drives global air circulation. As high-pressure systems rush in to take the place of low-pressure areas, heat and moisture are transferred resulting in differing climates in different locations.

3	Essential Question	What causes the patterns of air motion on a global scale?
3	Big Idea	Air currents, salinity, and solar radiation drive ocean currents around the world.

4	Essential Question	How do natural and manmade landforms affect climate and weather?
4	Big Idea	Proximity to water and elevation can dramatically affect the climate in a location.

5	Essential Question	How do humans affects microclimates?
5	Big Idea	Micorclimates are zones where the climate differs from the surrounding area (such a large building or near cities.) Building height and placement and manmade pollutants can alter microclimates.