Age of the earth and relationship to belief systems part of Dilemmas
In order to fully understand Earth processes such as plate tectonics, mountain building, erosion, evolution, and various time scales of global climate change students must have a firm grasp of geologic time and the age of the Earth. Mary is a student in science class for teachers. In a reflective writing assignment Mary reported that she did not believe that the Earth was 4.6 billion years old and constructed a list of young earth arguments that indicate an age of ~6,000 years.

Too Cool for Science part of Dilemmas
On a frigid Minnesota afternoon, I had just finished a mini-lecture in my introductory class, and I threw out a question to the whole class. Chris responded enthusiastically with a wonderful and correct contribution. At which point, Sam groaned and said, in a voice audible to the entire class,"suck up!" A few other eyes rolled, and other hands that had been raised were slowly lowered.

Al's bandwagon part of Dilemmas
In the eight person seminar class is an inquisitive, nontraditional, student who is a motivated popular science reader. This student challenges the conclusions made by the vocal majority of scientists that global warming is caused by human activity.

Meteorology Professor Bob part of Dilemmas
In an upper-level meteorology class, Meteorology Professor Bob introduces complex equations including calculus. A growing body of students strongly resist using mathematical skills that should have been mastered in the prerequisite mathematics courses. The instructor explains the context and necessity of these equations for understanding meteorology at the upper-division level. A common statement of students is: "I don't do math." Students insist they love meteorology but dislike math and lobby the department head for a graphical approach without the use of equations.

Avoiding hopeless paralysis part of Dilemmas
In an intro class, I wanted to engage students and show them the importance of the field of geology in their lives. So I presented the evidence for an imminent peak in world oil production and explained how oil forms, how long that takes and how difficult it is to find. I followed the bad news with some good news about research into energy efficiency and alternative energy sources. I assigned the students to write minute-papers at the end of class about this lecture.

Is planetary change bad? part of Dilemmas
We hear about global warming as a problem and there is a reasonable consensus that humans are exacerbating the problem. Our global population is currently about 6 billion, and scientists estimate that the planet's capacity to sustain ends at about 12 to 15 billion. Doubling time is 38 years. Next examine the core profile. Tundra pollen lies in the lowest layers, sage and prairie grasses in the middle and spruce and pine pollen in the top.

The Legacy of "We've always done it this way" part of Dilemmas
Joe recently completed his PhD and has landed a tenure track faculty position in the geology department at "Research U" for the fall semester. Joe will be teaching a large introduction to physical geology course in the spring. Research U has a variety of resources to help Joe develop his course and integrate the "affective domain," active learning, "clickers," etc. into his teaching. However, the department has a strong emphasis on research and views innovative teaching as not a priority. While in graduate school, Joe TAed both lower level introductory lectures and an upper level lab class, but received no formal training in teaching and was encouraged by his research advisor "just get by teaching."

Irrecoverable Failure part of Dilemmas
The course is an Earth Science for Teachers course. The content is outlined in a popular 16-chapter introductory text. Licensing for teachers specifies a certain block of content to be covered, which is about 12 of the 16 chapters. The professor gave two high-stakes (counted for grade) quizzes to prepare students for their first test, over four chapters, which is an essay exam. Quiz grades were low, so the teacher chastised the class about being unmotivated and urged them to study more.

Meeting learning goals with a below average course part of Dilemmas
During the fall 2006 semester I taught a first year writing seminar entitled "The World's Oceans in the Global Environment," a course designed to introduce students to important topics in marine science in the context of Earth systems science, as well as key issues in ocean policy (e.g., fisheries, implementation of marine protected areas, etc.). As a writing seminar, most student work during the semester was in the form of writing assignments.

Water Conservation versus Ecosystem Preservation part of Dilemmas
Nearly all of the water in the Colorado River system is removed for agricultural, industrial, and residential uses before it reaches the mouth of the river. However, the water delivery system in southern Arizona and California has a number of leaks (mostly seepage through the bottom of unlined canals), by which some of the water moves through the subsurface and back into the lower reaches of the river, sustaining a limited ecosystem in the Colorado River Delta.