This essay describes how interclass collaboration in the context of an in-depth interdisciplinary discussion and analysis of global problems can yield significant benefits in the development of ESL students' sense of efficacy, their literacy, and their critical thinking skills. Collaborative lessons expose the students to new and varied perspectives on the issues studied, creating a stimulating atmosphere of interactive learning. By encouraging students to interpret information, and to form, articulate, and support their points of view, the lessons enable them to gain skill in knowledge synthesis and application, two areas that are critical to success in college courses. In addition, collaborative discussions teach students that their opinions are valuable and worthy of consideration, thereby increasing their overall sense of efficacy. (Contains 7 notes.)