Archive for the ‘Education’ Category
Computer Programming – The Rules of the Game
A basis of a vector space is a set of vectors in that space that can be used as coordinates for it. [1]
I just read Dan Meyer‘s quick review of the Graspable Math tool. While I did briefly investigate Graspable Math, and also glanced at Desmos, the tool where Dan is head of teaching, what really struck me was how Dan’s writing shows him to be “on the inside” of math teaching and learning. As I am too. That is, there’s a room called “math”, both of us are inside it, and we’re familiar with the rules of the game.
As I love computer programming and am always looking for new ways to teach it, the question arose in my mind: what is the minimal set of constructs to teach students so that they can take off from there and learn the rest of computer programming, in any language, pretty much by themselves?
I did a quick search for “minimal constructs of programming” and found Software Design & Development: Programming Constructs (pdf) from The High School of Dundee in Scotland. Nice and clear, but according to the table of contents, roughly 30 topics. That feels like too many to be minimal.
When faced with the question of how to teach, I usually first turn back to myself – how do I learn? That answer is not likely to be the best or complete answer, because most students are not me. (A valuable lesson for teachers, that I struggle to keep in mind!) But it’s an OK start, and often it’s all I have.
When I learn a new programming language, what constructs do I look for?
- Variables (scalars, vectors; and assignment – same “=” sign means something very different from math)
- Operators (may look very different in, say, Python vs APL vs AWK)
- Conditionals
- Loops
- Input/Output
- Functions (could be an intermediate level topic, but so important for clear code that I put it here)
Maybe also
- Imports (to get access to additional commands)
- Classes (for object-oriented programming — question whether that’s an essential or advanced topic)
And there’s also environment and tools:
- How to edit
- How to compile (if necessary)
- How to run (both in editor and from command line — so “command line” is a concept too)
- How to interact with the program (where do I put input? where do I see output?)
The absolute minimum count of the above is 10 topics. Is that the minimum? Is that the right set? And, is it a set of topics where each one makes sense to a student who is new to computer programming? That last one is so important because (as above), my students are not me.
Thus, towards a second draft of the list, and maybe some hints to what kinds of explanations, exercises, and even learning-support tools (like the math environments mentioned at the beginning of this post, only for computer programming), I want to consider the question in some new ways. Based less on how I learn computer programming, and more on how people, even children, learn things from each other:
If computer programming were an outdoor game played at recess, and I were ten years old, how would I teach my friends the rules of the game?
If computer programming were a dance, what would be the basic steps?
What are your answers to these questions?
Writing, Unschooled
(credit: Google search “prompt definition”)
“Leap, please,” cried the young orangutan, holding onto his mother’s feral arm.
Do You See What I See?
Recently I found an excuse to dust off some old lab books of introductory science experiments. They were the curriculum for a 9th grade Physical Science I class at my high school; I wrote them as a summer job during college. I didn’t invent the experiments. Rather, the head teacher gave me outlines, and my job was to try them out and make sure they would work, so that prospective students wouldn’t get frustrated and turned off by science.
The excuse was a friend, a scientist, who is meeting a public service requirement of her studies by volunteering to teach science to schoolchildren, and to their teachers. I offered my science course as possible material for her classwork. As we looked over the experiments, we doubted a bit how even 9th graders might learn from them, or be as excited about them as I was when I built and tested them myself. Sure, the projects were easy, and they had worked. But would the experience of building these projects — static electricity demonstrations, electromagnets, motors — be enough to convey the principles behind their operation? Would the kids see the point?
Yesterday I was in the kitchen preparing a simple lunch of tacos and beans. Washing and cutting lettuce, chopping an onion, peeling a cucumber, grating cheese, warming the beans with some tomato sauce. In the quiet afternoon, I couldn’t help noticing the crunch of the knife through the lettuce. Or wondering how best to preserve the other half of the cucumber, now leaking water from its open end. And why do we grate cheese? So much science, here in the kitchen!
Now with the internet, you can search “science in the kitchen” and get pages and pages of websites with all sorts of neat science projects in the kitchen. Let alone YouTube with some pretty exciting and dangerous experiments. (Be warned!) I have no doubt that school science textbooks have taken this to heart and now include experiments that relate to the real world. And yet, science enrollment declines.
Even with the best of intentions, popular science experiments in the kitchen won’t do it. Science is not in school, nor is it in the kitchen. Science is not an activity, but a way (just one way) of looking at the world and making sense of it. What excited me in science class was not the sitting and listening to the lecture. It was making the connections with daily life outside class, and enjoying the beauty of the natural world with new understanding.
Those understandings could come from things as simple as basic cell structure in biology. There’s lots of water in a living cell, so when you peel and cut a cucumber, it gets wet. Or as complex as thermodynamics. One college winter, I learned that there’s really never a flow of “cold”, but only heat transfer. For a good month after that, climbing the steps to class, I would grasp the banister outdoors, and instead of feeling cold, I felt the heat flowing out of my hand into the metal. These experiences are what brought me back to study even more.
Science teachers have to have and share that excitement. If they’re not science experts themselves, no matter. They are learning adults, who can build their own understanding and catch the excitement from science mentors. The key has to be in giving the right answer to the question so many students ask: “But what is this good for?” The wrong answers are the allegedly practical ones — advancing technology, getting a job, or passing the test. The right answer, the one that should guide science teaching, and bring the kids back to class, is “Because the world around you is beautiful, and science gives you eyes to see it.”
No Free Lunch
Recently I read an article by Norman Balabanian (“On the Presumed Neutrality of Technology”, IEEE Technology & Society magazine, reprinted Winter 2006, pp. 15-25; originally published in 1980), where he addresses, among other things, the popular claim that people choose new technologies out of free choice. That if we use a technology, whether it be a car, or a refrigerator, or permanent-press clothing, we freely choose the benefits, and have accepted the costs. In several examples, Balabanian shows that we do not. We live modern life as part of an interlocking, consumption/profit-driven system which requires us to accept most of the new technologies, or starve.
I decided to do a small experiment in the household, to see up close what Balabanian was talking about.
The Experiment
I set out to collect and put aside all the food packaging that our family opened and threw away as part of our meals at home for one week. Not paper plates or napkins, or non-food trash such as newspapers. Just the containers that our food comes in. My kids wondered at first, but after a day or two I convinced them that even after school people still learn, and this was my self-assigned science project this week. As material rapidly piled up, I cut off “data” collection at 4 days.
What did I find?
I collected a half-full garbage bag of paper and cardboard, similar of plastic bags and bottles, and a few metal cans, for a total of 1 kg of waste material. By weight, the packaging was a bit less than 4% of the food net weight. Not much at all, but I was not concentrating on waste vs. recycling.
Rather, I was looking at the question: have we freely chosen to buy our food packaged?
Looking at the list below, I have to say “no”. Very few of these foods are available for purchase either at our corner grocery, or our large supermarket, without the packaging (i.e. take in your own container).
Reminds me of a cynical saying we used to have in high school: “You have a choice … and it has been made for you.”
The Challenge to Innovators
Don’t tell me how to recycle these materials. (We do already—as much as our city provides for.) That’s more forced choice: take the food in packages, and then recycle the packages.
Instead, suggest ways that we or the food distribution system could change so that we could eat our (reasonably) healthy diet without all the packaging in the first place.
Appendix 1: Four Days of Food Packaging
Food Amount (g) Type Wrapper Type Comments
Cheetos™ 55 Prepared Plastic Silverized
Pudding 330 Prepared Plastic
Fruit 1000 Prepared Plastic Styrofoam
Flour 2000 Prepared Paper
Cola 3000 Prepared Plastic
Milk 3000 Raw Plastic
Cereal 1200 Prepared Paper Waxed cardboard
Cereal 0 Prepared Plastic
Cottage Ch. 250 Prepared Plastic
Sugar 1000 Raw Paper
Potato Chips 50 Prepared Plastic Silverized
Eggs 1400 Raw Paper Cardboard
Soda Water 1500 Prepared Plastic
Smoked Salmon 100 Prepared Plastic
Granola 500 Prepared Plastic
Brown Sugar1000 Raw Paper
Yogurt 450 Prepared Plastic
Fruit Juice3000 Prepared Plastic
Margarine 2000 Raw Paper Waxed paper
Tuna Fish 320 Prepared Metal
Pineapple 825 Prepared Metal
Crackers 325 Prepared Plastic Silverized
Egglplant Spread 1000 Prepared Plastic
Mineral water 3000 Raw Plastic
Total Food Weight 27305
Talk About Quality 