Training, part 4: Live code demos

February 26th, 2011

You may think of live coding as a necessary evil: the thing you have to resort to when a connection fails and you can’t get at a running example, or when someone asks a question you’re not sure of the answer to and you have to try it out in real time. Admittedly, memories of coding in public (especially the connection-failure ones where you end up writing an entire Rails application on the spot…) are not always pleasant memories.

But I’d encourage you, as a trainer, to embrace live coding. Don’t wait for things to go wrong before you do it; weave it into your presentations and examples by design. You’ll find that the rewards are well worth the risks, and that the risks can be successfully managed without too much effort.

Live coding in presentations and Q&A

Live coding usually doesn’t happen in silence (except when something’s gone wrong). I use it in tandem with answering questions and presenting topics. I think with my fingers; I’m more comfortable and confident saying things about code while I’m writing code. Whether you’re that way in general or not, live coding can keep things lively in your classroom.

Sometimes the answer to a question doesn’t come to me unless I can do some typing; sometimes the answer comes to me but wouldn’t mean much or be clear enough without live code to illustrate it. I’ve never had the impression that anyone thinks less of me as a programmer or as a teacher because I’ve resorted to trying something out before answering a question. Furthermore, the technique of trying things out is, itself, an important one, and a good lesson for your students to learn. “Is Hash#update a destructive operation?” someone asks. “Let’s ask Ruby,” I reply, and then try it out on the screen in irb. (By the way, update is destructive. So is merge!. But merge isn’t, and there’s no update!. No wonder I have to keep checking.)

“Let’s ask Ruby” is a good slogan to keep in mind, and a good one to impart to your students. I’m always surprised when someone sends a question to a Ruby mailing list that could easily be answered by typing a few characters of code into irb. But it does happen; apparently the trying-it-out habit isn’t ingrained in everyone, and the classroom situation is a good place to try to instill it.

As for live demos during presentations: I show code snippets and examples on slides, but I often end up tabbing away from the slides into a console session and showing live examples of the language features and idioms that the slides describe. In this context I see live coding as a kind of bridge between static presentation and having the students themselves do some coding. Obviously having me code isn’t the same as having them code; but I believe that seeing me enter code on the screen encourages them to do the same, to an extent that seeing a static example doesn’t.

Managing risk with semi-live coding

There are certain things I don’t like doing from scratch live. Deployment with Capistrano is one of them. It never seems to go right all the way along. I’ll take the fall for this—I have no reason to assign blame to Capistrano—but I have to live with the fact that live Capistrano installaton and setup demos are, for me, risky.

So I do my live demo of Capistrano, but I do it with the help of a list of steps, written on a piece of paper, and I prepare a certain amount of it in advance. (It’s the permission settings and passwords that always get me.). I don’t hide the list of steps from the class; there’s no detrimental effect to their seeing it, and if they think my use of a script like this means that I’m inadequately skilled, then at least now they know!

Having the demo scripted reduces the risk, if not to zero then at least pretty close. Deciding when you need this kind of aid is up to you. For me it’s Capistrano; for you it might be something else. The main thing to remember is that the usefulness of a live demo for the students is that it’s dynamic and engaging. It doesn’t matter if you use a “cheat sheet”, any more than it matters whether a pianist plays by heart or from the music, as long as the performance is good.

The “cheat sheet” technique applies mainly to fairly complex code demos that you can predict and plan in advance (as opposed to those that you do spontaneously in response to a question, or as a sample illustration of a language feature). Losing your way in the demo isn’t the only risk of a lengthy demo, though; there’s also the lengthiness itself. You don’t want to get embroiled in irrelevant details, nor to start boring the class.

Managing lengthy demos with the cooking-show approach

I draw inspiration from television cooking shows, in the matter of dealing with code demos that might otherwise be too long or detailed. These shows often use a kind of time-lapse technique. The chef mixes some ingredients and gets everything to the point of putting it in the oven. Then, instead of waiting in real time for the cake to bake, the chef produces a finished cake that’s been baked beforehand. The lesson can then resume at the point of frosting the cake.

The cooking show approach can be very handy for in-class demos. It’s particularly suited to cases where you want to demonstrate how to do something relatively small, and then want to show how it fits into a finished application. Rather than have the students sit through the writing of the whole application, you can write the bit you’re talking about—a data validation directive in a Rails model file, perhaps—and then run the whole application and show that it fails when the data is invalid. Or you might walk through the creation of one class or module, but then have the others already prepared so that you can fast-forward.

On cooking shows, the fast-forward technique might apply to the overall process (baking a cake, say) or to a subprocess that doesn’t lend itself to real-time presentation, like waiting for dough to rise or chopping large quantities of onions. The TV chef might illustrate the chopping technique, but then pull a bowl of pre-chopped onions out of the refrigerator and thus condense the time-frame.

The same thing applies in training. The time lapse you incorporate may involve a whole application, or it may involve a repeated task at one level of abstraction, analogous to chopping onions. By all means do a live demo of adding a “has_many” association to one or two of your models. But if you’ve got a lot of such cases in your sample application, consider doing most of them in advance and leaving just those one or two to do as a live demo.

So keep your irb session open, even during your slide presentations, and think creatively about semi-live and cooking show-style demos. Live coding keeps things in the moment, and adds motion and interest to the features you’re trying to put across.

There’s no such thing as pure lecture in my technical classroom. From the very beginning I encourage students to open up program files and interactive interpreter sessions and play with them while I’m talking. Meanwhile I’m often bouncing from a bullet list on a slide, to a console where I demonstrate a coding technique in real time. And much of the time I’m not even presenting; I’m walking around the room helping people with their hands-on exercises.

In writing about modes of instruction—lecture, demo, hands-on or “lab” mode—I am drawing artificial boundaries. In the classroom it’s actually a blend. But bear with me; the artificial boundaries aren’t entirely artficial, and they allow for some salient and helpful points to be made.

In today’s post I’ll be talking mainly about lecture mode: the part where you’ve got the class’s attention and you’re sitting there saying stuff and showing slides and writing code in a file or console. In later posts we’ll look more closely at some specific points about code demos, as well as some ideas for making the most of hands-on exercise time. This time around we’ll focus on the verbal and its cognitive underpinnings.

The teacher’s “advantage”: the z-axis

The biggest problem people face when speaking to a class about a topic is trying to say too much. In fact, it’s largely for the purpose of isolated and tackling this problem that I’ve separated lecturing out as its own topic.

Consider a lecture snippet that consists of the following two points:

To create a Ruby hash, put the keys and values in curly braces.
You separate keys from values using the so-called “hashrocket”, '=>'.

Never mind for the moment what’s being projected on the screen (maybe bullet points, maybe a live code demo). The teacher wants to make those two points verbally about hashes.

Now here’s what happens: a feeling of guilt kicks in, a kind of full-disclosure compulsion. How (one’s teacherly conscience prompts one to ask oneself) can I mention curly braces as literal hash constructors, and not at least mention that they’re used for other things?

So now we’ve got two main points and an aside, with the main points flowing into each other and the aside understood to be in parentheses, so to speak:

To create a Ruby hash, put the keys and values in curly braces.
    (Curly braces are also used for code blocks, but that's a
    different usage.)
You separate keys from values using the so-called “hashrocket”, '=>'.

But you still feel like you haven’t done your pedagogical duty; or maybe that voice in your head is telling you that if you don’t say at least a little bit about operator overloading in general, as a kind of placeholder, your students will later come to feel that you omitted an important topic reference. So, for either nurturing or self-protective reasons, we get an aside inside the aside:

To create a Ruby hash, put the keys and values in curly braces.
    (Curly braces are also used for code blocks, but that's a
    different usage.
        (Lots of operators are overloaded in Ruby -- square
        brackets, for example.))
You separate keys from values using the so-called “hashrocket”, '=>'.

You know you’re digressing but you’re confident that the main topic is moving forward effectively and that the digressions will serve as useful placeholders for later discussion. You have no doubt that what you’ve done amounts to the utterance of two main points, with a bit of embellishment but clear and communicative nonetheless.

In other words, you perceive the asides as occupying a space somehow different from the space of the main points; you perceive them along a kind of z-axis, oblique to the main axis of exposition—something like the axis of depth shown here:

Digressions stand apart from main points in teacher's mind

The only problem is that what your students are actually hearing—what they, rather than you, perceive—is more like this:

Students hear topics and subtopics in a flattened way

The lesson? Have mercy on your students. They’re probably smart, but they don’t have the necessary experience in the topic to evaluate, as your verbal presentation unrolls before them, what’s a main point and what’s a digression. They don’t have the background, so to speak, to pick out the points in the foreground.

Sure, if you make an aside about Led Zeppelin or how to bake bagels, they’ll get that it’s an aside. But if you chase down every little technical opening or clue in your own speech, if you pepper your exposition of a subtopic with points from elsewhere in the general topic, it will only serve to confuse your listeners and add to their anxiety about mastering the subject matter.

When in doubt, lie

In the preface to The TeX Book, Donald Knuth has this to say about topic flow:
Another noteworthy characteristic of this manual is that it doesn’t always tell the truth. When certain concepts of TeX are introduced informally, general rules will be stated; afterwards you will find that the rules aren’t strictly true…. The author feels that this technique of deliberate lying will actually make it easier for you to learn the ideas. Once you understand a simple but false rule, it will not be hard to supplement that rule with its exceptions.

Lecturing without filling in all the details that you know are lurking in the topic feels like lying. It’s OK, though. In fact it’s your responsibility. You’re not really going to say everything, even if you try to cram some extra points in. All these digressions are no more than token efforts, when measured on the scale of the full complexity of your topic. So treat them very skeptically when they present themselves to your brain for delivery to the class.

I don’t mean that you have to become robotic or cleanse your speech of every molecule of outside reference. (Your students won’t let you do that anyway, once they start asking questions.) But try to shake the feeling that you have to cover the entire canvas with your brush on the first pass through. The learning canvas is random access; you can come back to things instantaneously at a later point when they fit in.

And remember that you are not being tested. A lecture is not an oral examination. Even in an oral exam you’d probably want to do more than just a brain dump; all the more should you pick and choose carefully what you say in lecture mode. No one is keeping score. They’re just trying to connect the dots and learn from you.

It’s tricky, of course, because subtopics do have circular dependencies and there are a lot of enticing sub-subtopics on almost any path through a topic. The art of lecturing on technical material (and lots of non-technical material, for that matter) is the art of presenting a non-linear topic in a linear way. Correspondingly, the discipline of lecturing is the discipline of not trying to say everything in the course of talking about any one thing.

Listening to yourself

When you’re talking to a class, you’re performing. I don’t mean you’re being a phony or putting on an act. I mean “performing” in a more technical sense. I’m a musician, so I understand this best in connection with music.

The most difficult and in some ways the most mysterious thing about musical performance is that when you’re performing, you’re also listening. It’s an instantaneous process: the listening part of you tells the playing part of you how things are going and what adjustments have to be made, yet somehow the adjustments aren’t exactly adjustments to anything because they precede the actual production. You can’t really listen to something you haven’t played yet, but that’s what it feels like.

Like I said, a mystery. Let’s leave it at this: performing means letting go but it also means carefully monitoring what you’re doing.

With experience, you learn to listen to yourself as you lecture. When I’m explaining something, part of my brain is creating and delivering the explanation. Another part is consuming it: I’m listening to myself and instinctively spotting the gaps, fuzzy spots, and glitches, hopefully before they happen. I’m also making quick, executive, performative decisions, perhaps literally as I’m drawing breath, as to what’s really relevant and what isn’t.

My impulses, for what it’s worth, tend fairly strongly toward the fill-in-every-detail direction; I need my inner musician (or my inner editor with a red pencil, if you like) guiding me and directing topic-traffic so that I can keep things moving forward. It works, too; but it’s something I had to become conscious of to master.

Presenting a topic with the right balance, the right arc, and the right (probably small) coefficient of digressions, means you’re truly in the teaching zone.

Next up: advice on code demos

For me, the most challenging thing about training is accomodating people who come to a class from different backgrounds and with different levels of experience and knowledge. So let’s dive right into that.

How different are different levels? At times, very.

I remember a Rails class whose members included a participant in that year’s “Rails Day” contest (i.e., a very experienced Rails developer), side-by-side with someone who had literally never written a computer program and never seen a command line. The latter person was a front-end designer, and I have every reason to think she was skilled and successful. But she did not belong in that class. (To be fair, the Rails Day guy probably didn’t either—except that he was actually there in part to help some of the other people in the class, who were his co-workers.)

Given a room with that diverse a population, what you can say? I mean that quite literally: what can you say? What sentence can come out of your mouth that’s going to make sense to everyone in the room and hold everyone’s attention? You don’t want to aim too high and confuse the less advanced people. But you don’t want to bore the more advanced students by aiming too low.

Managers sometimes err (quite understandably) on the side of sending more rather than fewer people to fixed-cost, on-site training courses; and even with public courses, self-selection based on advertised course requirements and content doesn’t necessarily serve to keep the group at one level. If you train, you’ll face this issue early and often.

Still, there’s a lot you can do to make the experience rewarding for everybody even in a very mixed-level group. Here are some suggestions—in no particular order except that the first one is the foundation on which all the rest, and indeed all of your training activities, must be built.

A. Deliver what you promised to deliver

This comes absolutely first and foremost. If the course was sold as a beginner’s course, then you have to provide a worthwhile course for beginners. If it’s an advanced course, you have to give the advanced students the best experience you can. Beyond this you can tweak and adjust; but delivering what you promised has to be the starting point.

Occasionally you’ll get a class where everyone is at the same level as each other and it’s not the level you advertised. That doesn’t happen often, but if it does, you can go ahead and recalibrate the whole curriculum. I did that once with a programming team who had much more experience than I’d been led to expect them to have. They were too polite to come out and say that they were too advanced for the curriculum, but it was pretty obvious. So we changed gears on day two and spent the remaining days on more advanced topics and code critique.

That’s a rarity, though. You’ll find the truly mixed-level class to be much more common, and whatever you do to optimize the experience for everyone, you must stay rooted in the curriculum you’ve promised to cover.

B. Make the prerequisites clear in advance

When you’re discussing the course skill-level with the client or prospective participants, show some tough love: be clear and firm about the prerequisites. It’s in everyone’s interest. Don’t try to be all things to all people. Use clear terms like “not suitable” or “too advanced” or “only right for beginners” if those terms apply.

Course prerequisites don’t have to be fine-grained, but they do have to be clear. “Everyone in the course should already be experienced with at least one object-oriented programming language” is an example of a reasonable prerequisite. So is “The participants need to be at least somewhat comfortable in a Unix-like environment.” You don’t need to know whether they know all the command-line options for grep. You just need to establish the basic requirements.

If you’re teaching a dependent technology—meaning, the way learning Rails depends on learning Ruby—address the role of the parent technology. You can teach Rails to people who know Ruby, or to people who don’t; but mixing Rubyists with non-Rubyists in a Rails class is problematic. Make sure you’re in accord with your clients about any assumed parent-technology baselines.

B. Try to control the teacher/student ratio

To the greatest extent that you can, keep the teacher/student ratio at 1/15 or better. Beyond about fifteen, in my experience, you hit critical mass: the amount of help needed by the students expands beyond the confines of the available time for one instructor, so you fall further and further behind.

This is ancient wisdom, of course. Universities like to brag about their tiny class sizes and all of that. And with training classes (as with universities, incidentally), you can’t always control it. But if you’re presented with, say, the prospect of providing hands-on, closely-coached technical training for twenty-five or thirty people, see if you can find another instructor—or at least a lab assistant who can troubleshoot software installation and other matters so that you’re not doing everything.

D. Have extra material in reserve

Try to have some ideas for extra projects up your sleeve, above and beyond any in your stated curriculum, particularly for students who are too advanced for the course. Bring a few books with you, and if someone isn’t feeling challenged enough, point them to a chapter that you think they can learn from. They won’t feel shunned; they’ll feel relieved. The whole problem is that the too-advanced person shouldn’t be there in the first place, so anything you do to help them not be bored is in their interest.

E. Enlist the help of the more advanced students

I’m thinking of situations where, say, one student is clearly over-qualified for the exercises in the workbook, and another student is struggling. It’s possible that the best course of action is for the over-qualified student to pair up with the struggling one and help them out.

This is a tricky strategy, though. It’s your job, not theirs, to do the teaching. The situation has to be really right before you ask students to teach each other.

But it often is really right. For one thing, teaching something helps you consolidate your own knowledge—so everybody wins, including the student-teacher. And some people would rather spend the time engaged in an activity with someone else than go off and work on an application or read a book.

As the teacher, though, you have to make sure that the result is at least as great as the sum of its parts: all parties involved have to understand and accept the plan. You don’t want it to backfire and have either student (or both) think you’re trying to brush them aside. Be circumspect about this option, but keep it in mind for the right situation.

F. Master the art of not answering questions

Don’t get me wrong: in general it’s good to answer questions. But when questions come from students who probably shouldn’t have taken the course in the first place, and are shifting the focus onto material that’s either too simple or too advanced, it’s your job to protect the class.

When I get a too-advanced question, I usually answer it quickly and, if need be, incompletely. I don’t want to digress too far from the curriculum—and above all I don’t want to make the less advanced students feel anxious because they can’t follow what I’m saying. You can always ask the advanced student to talk to you about their question later; but you only have one shot at making the dynamics of the classroom work for everyone. So answer the question quickly; offer to go into it privately later; don’t get into a lot of examples and demos based on the question (that can really make the other students feel abandoned); and move on.

Too-basic questions can be harder to deal with than too-advanced questions. In fact, it may be through such questions that you first discover that some of your students are under-prepared. This may be a good time to consider a temporary ad hoc student-teacher system (see E., above) where someone else in the class helps the person, assuming it’s something that can be communicated relatively quickly (like how to start Ruby from the commandline, creating a MySQL database from scratch, etc.).

G. Make it easy to move around the materials (e.g., staged code shapshots)

For the main do-as-you-go application in my Rails workbook, I’ve got twelve code snapshots. Each one represents the state of the application at a particular point in the book. If a student falls a bit behind, or wants to skip a section they already know about, they can move to a later chapter or section and “fast-forward” by swapping the appropriate code snapshot into their working code directory.

Furthermore, if I need to fast-forward through a topic, I can then pick up from a particular code snapshot and keep going. I might do this with a couple of topics if, say, a client has asked me to deliver a four-day course in three days—or if I’ve just fallen behind a bit and want to get the class back in sync with the courseware. (I don’t make a habit of falling behind but I do try to provide enough material that compressing one or two subtopics won’t be a tragedy.)

Staged code snapshots aren’t the easiest thing in the world to maintain, but they’re a good example of adding an element of independence to the classroom experience for students who want to adjust the pace.

H. Talk to the person in charge

I’m thinking here mainly of private, on-site training engagements (though the principle could be extended to on-going discussions with individual students too). You’ll probably have a discussion at the beginning and/or end of each day with the manager who set up the training. You should definitely bring any issues about class preparedness level to that person’s attention.

When you do, you’ll find that ninety-nine percent of the time the manager will say something like, “Yeah, I was afraid that it would be too easy for Julie” or “Bill said he’d learn Ruby on his own over the weekend but I guess he didn’t.” The manager knows the team. None of what you say is going to be a huge surprise.

Be sympathetic, though. The client didn’t do this to make your life hard. At worst, they just didn’t think it through in terms of preparation and were eager to get the most value out of your skills. Everyone’s acting in good faith.

Sometimes, the manager will take someone out of the training after the first day. I always feel a pang of guilt at this—but I shouldn’t, and you shouldn’t. It’s a correction that will make things easier and more productive for everyone, including the person who shouldn’t have been in the training in the first place. Of course you want to challenge yourself to make the experience accessible to and meaningful for as many people as you can. But don’t be Utopian about it; there really is such a thing as a person for whom a given class at a given time just isn’t right.

Summary

Here’s a summary of the suggestions we’ve just gone over:

  • A. Deliver what you promised to deliver
  • B. Make the prerequisites clear in advance
  • C. Try to control the teacher/student ratio
  • D. Have extra material in reserve
  • E. Enlist the help of the more advanced students
  • F. Master the art of not answering questions
  • G. Make it easy to move around the materials (e.g., staged code shapshots)
  • H. Talk to the person in charge

Handling the mixed-level classroom successfully is not easy. You need to stay alert and to keep applying energy to the situation to make it as good as it can be for everyone, while delivering what you promised to deliver. A mixed-level group requires agility and adaptability, but with structure.

Some of the training companies I subcontract with do Likert scale evaluations (“Strongly agree, Agree, Neutral…”—that kind of question). One of the questions is often about the pace of the class: much too slow, too slow, perfect, etc. In a mixed-level class, I don’t expect everyone to say the pace was perfect. I aim, though, for the mathematically best result possible: I want the curve to max out at “perfect” and fall away (hopefully not too far) to the sides.

Then I know I’ve done my best.

Training: a series introduction

January 24th, 2011

This introduction is the first—number zero, if you like—in a series of articles about technical training, intended to be read by trainers but of interest, I hope, to a variety of teachers, managers, and interested learners from various backgrounds. After this introduction I am planning at least three further articles, addressing such topics as how to handle classes with mixed levels of experience and what’s involved in choosing among different teaching modes (lecture, hands-on, etc.). After that, we’ll see.

Not all teaching is training. But as far as I’m concerned, all training is teaching; and teaching is a fascinating, challenging, absorbing art. I’m not going to philosophize at any length about the terminology. I just want to make it clear that in this series about training, I consider myself to be addressing a branch or style or permutation of teaching, with all that that implies.

I’ve taught a lot and I’ve been at it for a long time. From 1992 to 2005 I was on the faculty of the Department of Communication at Seton Hall University, teaching media history and research to undergraduates. Meanwhile I’d been programming computers as a hobby since 1972 (with some gaps, but pretty steadily since 1990), and I’d become a Ruby and Ruby on Rails expert.

By mid-2005, my academic career and my supposed hobby were on a collision course. I had a year-long sabbatical coming up, with the expectation that I would write an academic book; but that summer I signed a (non-academic) book contract with Manning for Ruby for Rails.

The timing was favorable for a change. Ruby beckoned; and with a sabbatical scheduled I wasn’t expected to be in the classroom anyway. So I changed careers: I resigned from Seton Hall, instead of taking the sabbatical, and started to earn my living as a Ruby consultant, author, and trainer.

I figured I’d finish Ruby for Rails and then get a programming job. I did finish the book, but instead of getting a job I set up a one-man consultancy, Ruby Power and Light, and started taking on short-term contracts—and a lot of training jobs. I trained and trained. In 2006, I traveled to something like twenty-three cities, from California to Sweden, training people in Ruby and Rails.

I continued to make my living mainly from Ruby and Rails training through most of 2009, at which point I started working full-time as a developer at Cyrus Innovation. I’m still involved in training projects, though, especially (though not exclusively) a recurring training event called The Compleat Rubyist. Teaching isn’t my main bread-and-butter at the moment, but it is a part of me and always will be.

I hope you enjoy the series.

Next up: Handling mixed levels of experience in a training class