From PZ Myers:
How do you design a new course?
First message: don’t. It’s a lot of work, and we professors are already underpaid and overworked. You do not get a bonus for teaching more, you are a salaried worker and you get paid whether you teach one course or five courses. You should be compensated for your labor, but you won’t, and in fact many of the institutions of university governance will conspire to discourage compensation for taking any initiative.
For instance, my university has a precisely defined formula for calculating workload: we plug in the number of lecture hours and lab hours we teach, and it spits out a number of credit hours we’re teaching, which is supposed to be right around 20 (different universities will have different expectations). We all know each other’s number. We strive to keep everyone’s workload equal, because that’s only fair, right? Of course, there are many assumptions built into the formula — the weighting of labs vs. lectures, for instance — and there’s nothing about the difficulty of courses. I could teach nothing but introductory freshman courses with no labs, while someone else could be assigned a set of new, advanced upper level lab electives, and we could have exactly the same number, but you know which of us would be working much harder. We informally try to balance that kind of load, but that magic number is really only a rough guideline.
It’s also a fiction for another reason: we fudge it to keep from breaking the system.