So, I'm teaching a course on Scientific Realism in the fall. I wanted to start off with a unit titled "What is a theory?" to make sure all of my students are on the same page and to prepare them for later topics.
The problem I'm having, however, is that most of the good articles I'm finding are fairly technical--- presupposing at least some familiarity with model theory. Since my students will be undergraduates, most of whom will have an intro logic course at best under their belts, I don't want to start off the course with something that will be far above their capabilities.
That being said, does anyone know of an article like this one by Frederick Suppe which might be a bit more approachable?
EDIT: There seems to be some confusion over what exactly I'm asking about. I'm not looking for an easy presentation of some particular scientific theory. Rather, I'm looking for a discussion of what a scientific theory is (e.g., a collection of partially interpreted sentences, a collection of models, etc.). See the linked Suppe article for an example. See the "About Theories" section of this wiki on Scientific Theory. I'm look for some free-standing academic articles ("pop science" books aren't really what I'm after) that explore those issues (syntactic vs. semantic construal of theories) without beating the students over the head with too much model theory.
FURTHER EDIT: Since two of the four answers currently posted are the answerer's own (or at least uncited) ideas, I feel the need to emphasize that this is a reference request. I'm looking for an article that fits the stated criteria. People's own ideas, while perhaps of value, do not help me at all here.