In the first two weeks, my signal processing class has...

Feel free to comment on any of these things, by the way! No guarantees as to how comprehensible the material is to folks not in the class, but... if something looks nifty but is vague, holler and I'll see if I can fill missing parts in. All our content, including homeworks and so forth, is open-licensed. (Thanks to Mike Heinz for licensing his MATLAB code GPLv3, which enabled us to open-license our last homework assignment tonight.)

It feels good to be teaching again. The classroom is where I first felt the meaning of the word "vocation" in my bones and not my head; I remember that evening. I was 19, running a ModCon tutorial at Olin, and it felt like there was fire pouring through me; the classroom environment, the questions and reactions and projects of my students, everything about that room flowed with a powerful magic, and I knew the alchemy was mine; I could ignite people, and it felt as natural as breathing.

I'd been teaching for a couple years at that point, and liked it, and was pretty good. But that evening was like nothing I'd ever felt or seen, the first full blast of a fluent symphony I'd only heard practiced in skillful yet labored passages up to that point. I remember walking out of that room, finding an empty hallway, and slumping against the wall in the half-darkness, breathing hard, trying to figure out why I was shaking. The plans and figures of my future life were shifting in massive ways I couldn't see or understand. It was my junior year of college, and my (extremely vague) career plans involved "product design in industry, or something" -- grad school wasn't really on the "or something" list, being a professor was still something Other People did.

And look what I'm doing now; I'm on the path to becoming Future Dr. Mel.

I think my friends and professors realized it before I did: I teach. I have to teach. No matter what I'm doing or where I am, I teach. And when I teach well -- whether it's in a classroom, or giving a conference talk, or through my writing -- that's when the thunder pours through my bones. It doesn't happen often, and it's only happened that intensely a couple of times in the 7 years since. I often don't remember the actual experiences as well as the coming-down feelings afterwards; falling onto my hotel room bed covered in sweat, leaning my forehead against the cold metal of a bathroom stall door feeling my heart rate pound itself slowly back to normal in my throat, shaking against the wall of another empty hallway, or another, or another.

I also remember clumsy tutorials and fumbled moments and aggravating nights of grading papers, tracking down late students, the anguish of not being able to reach or help someone, learning (with difficulty) how to set boundaries so I wouldn't drain all my energies trying to help my students and would actually complete my own coursework (there are dangers to the love of teaching). Or talks I could scarcely get myself to give beforehand, pacing my room and trying to stop hyperventilating. Or things I've written that wouldn't come, or splurted out in the wrong way, or tangented off in tumbled words, or that I just became sick of looking at, thinking about. There were many bleary-eyed evenings when I wondered why I was bothering at all. And then I'd step into the classroom or on the stage or behind the keyboard and the thunder would come -- even faintly, for a moment -- and I remembered that my answer was a thousand times yes, forever.

Because I think that's all that you can say to a vocation, even one you're still trying to pinpoint (and sometimes it's a moving target). You take your calling with both the glory and the slogging mundanity it brings; you find what you're built for, and then you rebuild yourself to do it better. Even here, in this writing -- I am tired; the words are not flowing well, they try too hard. And I am halfway through grading, which I would really rather not be doing. And... well, you know. It's part of the package of a craft you can't not master.

I think the thing I love the most about teaching is that it is, more than anything else, a way of giving, a pouring-out of yourself.

I think I need to stop writing and finish up my grading now. I'm... I'm losing coherence and focus, and this is a stumbling and awkward post. But ah, teaching. I've missed you, classroom. Hello again. I'm... I'm a Mel.