The purpose of this study was to (a) understand how students view similar issues from a local vs. a global perspective, and (b) to document how a science-based class can change opinion about environmental issues. A total of 8,523 students provided opinions to three paired statements about deforestation, over-population, and pollution at the beginning (Week 1) and end (Week 15) of the course. The first portion of each paired question dealt with the issue from a global perspective, and the second portion of each paired question dealt with the same or similar issue from a local perspective. Students believed that tropical forests (global issue) should be protected regardless of costs; however, a majority of these same students did not support the protection of old growth forests in the Pacific Northwest (local issue). More than 70% of students agreed that over-population is one of the world's most pressing environmental issues (global issue), but it was a less important local issue. Greater than three-quarters of students agreed that, on a worldwide basis, pollution has become worse in the last 25 years (global issue), but it was not an important local issue. Student opinion shift was measured by comparing student opinion at the first and last week of the semester. Student opinion significantly changed for all of the six survey statements. By the end of the class, student opinions were more aligned with the science associated with each issue.