Good article here at the Chronicle on balancing teaching with research, from a neuroscience professor who makes it work for him.
The reality of modern academe is that, no matter what your institutional affiliation, the time you can devote to research is being squeezed by multiple competing demands. No simple solution to that problem exists for any of us. But I have found that rethinking the nature of our professional commitments, such that teaching activities bleed into research ones (and vice versa), can be an effective way to reduce the time crunch. Academics describe their workload of scholarship, teaching, and service as if those were entirely separate entities. In reality, the line between teaching and research is usually much fuzzier.
Read the whole thing, in which Prof. Gendle writes at length about the potentially prosperous symbiosis between teaching and research. He points out three key scholarly skills which teaching reinforces: developing your presentation skills, responding appropriately to odd questions, and making connections across fields. He emphasizes his success in maintaining an active research agenda while keeping a “moderately heavy” teaching load, which for him is 5-6 courses per year. My teaching load is 8 courses (6 preps) per year, and to that situation Prof. Gendle says:
I am fortunate that my teaching load still allows some dedicated time for research. That may not be the case at institutions with teaching loads of seven or more courses in a single academic year. Teaching loads of that magnitude often pass a tipping point for most faculty members (myself included). With that many courses, there simply are not enough hours in the day to conduct classes, grade papers, etc., and still have time left for research.
Gendle is in the psychology department at Elon University, which is well-known for being an undergraduate institution with a reputation for engaging students in meaningful scholarly work.
Do any of you teach at institutions with a 7+ course-per-year teaching load, and still manage an active research program of some sort?
Casting Out Nines 
I have a five course load, but would like to note an important part of an active research agenda: REJECTIONS! Whether from granting agencies, journals, book publishers, doesn’t matter. I can tell my students–especially in the writing-intensive class–to learn from bad grades, just as I learn from rejections. It seems to help.
@John: You’re right, and what students find interesting is not only that professors have to deal with rejections, but that for us, the only thing more disappointing than negative feedback is a rejection with no feedback at all. I was a PI on a grant my college recently submitted to a funding agency and we were turned down — with no indication of what the issues were or why we were rejected. How are we supposed to get funding for this thing, or submit a better proposal next year? Students tend to gloss over professors’ feedback, and they are a little surprised to learn that feedback is valuable, positive or negative.