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I’ve just agreed to be the head judge for a LEGO robot competition for high school students.  In light of my workload this year, that probably means I have lost my marbles.  However, I couldn’t resist.  I judged last year and found it extremely interesting.  I’m looking forward to meeting others in the province who love the combination of kids and robots, working with the judges to develop a consistent way to score teams’ performance, and just getting off campus more.  Of course, if I ended up recruiting kids into my program, that wouldn’t be so bad either).

Acadia University hosts the local FIRST LEGO League competition for 9-14 year olds, which is co-ordinated internationally.  Four years ago, they decided to run an  independent high-school competition so that kids who had aged out of FIRST could continue to compete.  To see the details, go to the competition page and click on High School Robotics.

My responsibilities are

  • defining the challenges (this needs to happen ASAP)
  • getting the word out about the competition, which is in February
  • answering questions from school teams about the competition and the challenges
  • helping with orientation for the judging team

The teams borrow or buy a robot kit and get three challenges to complete — things like moving pop cans, dropping balls into containers, detecting and navigating around obstacles, etc.  The teams get two runs through the course, with time in between the runs to make changes to their robots.

How Teams Are Evaluated

  1. An interview with two judges before their robot runs the course.  They have to explain their code, demonstrate their robot, and answer questions about their process
  2. An interview between the two runs.  They have to explain what went well, what didn’t go well, and how they are going to improve.

Things I Noticed Last Year

  1. The teams tended to be well balanced — either the students were all able to explain each aspect of the robot, or each student was able to explain one aspect in detail.  There was the occasional student who didn’t seem to be as involved, but not many.
  2. The coaches varied widely in their degree of involvement.  There were some programs that I was pretty sure the teams wouldn’t have come up with on their own, but they seemed able to explain the logic.
  3. Almost all the robots performed poorly on the competition field, with many of the planned features not working.  This surprised me, since organizers publish the exact dimensions and features of the competition field months in advance.  Surely if the design was not meeting the requirements, the students knew that in advance…
  4. Some teams were able to articulate what exactly was not working after their first run (for example, the robot ran into the wall and then couldn’t turn around), and some teams were not.
  5. Regardless of their ability to diagnose the problem, most teams were not able to troubleshoot in a logical way.  The changes they proposed to improve for their second run often addressed an unrelated component — for example, if their robot had incorrectly identified the difference between white and black cans, they might propose to change the motor speed.

For those of you who’ve participated in robotics or similar competition, any suggestions?  I’m especially interested in these questions:

  • What helps new teams get involved?
  • What features of the challenges can help kids think independently and algorithmically?
  • What practices in the design or judging can promote more causal thinking?

Last February, I had a conversation with my first-year students that changed me.

On quizzes, I had been asking questions about what physically caused this or that.  The responses had a weird random quality that I couldn’t figure out.  On a hunch, I drew a four-column table on the board, like this:

Topic: Voltage

Cause

Definition

Characteristics

Formulas

 abc

I gave the students 15 minutes to write whatever they could think of.

I collect the answer for “cause” a write them all down.  Nine out of ten students said that a difference of electrical energy levels causes voltage.  This is roughly like saying that car crashes are caused by automobiles colliding.

Me: Hm.  Folks, that’s what I would consider a “definition.”  Voltage is just a fancy word that means “difference of electrical energy levels” — it’s like saying the same thing twice.  Since they’re the same idea, one can’t cause the other — it’s like saying that voltage causes itself.

Student: so what causes voltage — is it current times resistance?

Me: No, formulas don’t cause things to happen.  They might tell you some information about cause, and they might not, depending on the formula, but think about it this way.  Before Mr. Ohm developed that formula, did voltage not exist?  Clearly, nature doesn’t wait around for someone to invent the formula.  Things in nature somehow happen whether we calculate them or not.  One thing that can cause voltage is the chemical reaction inside a battery.

Other student: Oh! So, that means voltage causes current!

Me: Yes, that’s an example of a physical cause. [Trying not to hyperventilate.  Remember, it’s FEBRUARY.  We theoretically learned this in September.]

Me: So, who thinks they were able to write a definition?

Students: [explode is a storm of expostulation.  Excerpts include] “Are you kidding?” “That’s impossible.” “I’d have to write a book!”  “That would take forever!”

Me: [mouth agape]  What do you mean?  Definitions are short little things, like in dictionaries. [Grim realization dawns.]  You use dictionaries, right?

Students: [some shake heads, some just give blank looks]

Me: Oh god.  Ok.  Um.  Why do you say it would take forever?

Student: How could I write everything about voltage?  I’d have to write for years.

Me: Oh.  Ok.  A definition isn’t a complete story of everything humanly known about a topic.  A definition is… Oh jeez.  Now I have to define definition. [racking brain, settling on “necessary and sufficient condition,” now needing to find a way to say that without using those words.]  Ok, let’s work with this for now: A definition is when you can say, “Voltage means ________; Whenever you have ___________, that means you have voltage.”

Students: [furrowed brows, looking amazed]

Me: So, let’s test that idea from earlier.  Does voltage mean a difference in electrical energy levels? [Students nod]  Ok, whenever you have a difference in electrical energy levels, does that mean there is voltage? [Students nod] Ok, then that’s a definition.

Third student: So, you flop it back on itself and see if it’s still true?

Me: Yep. [“Flopping it back on itself” is still what I call this process in class.] By the way, the giant pile of things you know about voltage, that could maybe go in the “characteristics” column.  That column could go on for a very long time.  But cause and definition should be really short, probably a sentence.

Students: [Silent, looking stunned]

Me: I think that’s enough for today.  I need to go get drunk.

Ok, I didn’t say that last part.

When I realized that my students had lumped a bunch of not-very-compatible things together under “cause,” other things started to make sense.  I’ve often had strange conversations with students about troubleshooting — lots of frustration and misunderstanding on both sides.  The fundamental question of troubleshooting is “what could cause that,” so if their concept of cause is fuzzy, the process must seem magical.

I also realized that my students did not consistently distinguish between “what made you think that” and “what made that happen.”  Both are questions about cause — one about the cause of our thinking or conclusions, and one about the physical cause of phenomena.

Finally, it made me think about the times when I hear people talk as though things have emotions and free will — especially high-tech products like computers are accused of “having a bad day” or “refusing to work.”  Obviously people say things like that as a joke, but it’s got me thinking, how often do my students act as though they actually think that inanimate objects make choices?  I need a name for this — it’s not magical thinking because my students are not acting as though “holding your tongue the right way” causes voltage.  They are, instead, acting as though voltage causes itself.  It seems like an ill-considered or unconscious kind of animism. I don’t want to insult thoughtful and intentional animistic traditions by lumping them in together, but I don’t know what else to call it.

Needless to say, this year I explicitly taught the class what I meant by “physical cause” at the beginning of the year.  I added a metacognition unit to the DC Circuits course called “Technical Thinking” (a close relative of the “technical reading” I proposed over a year ago, which I gradually realized I wanted students to do whether they were reading, listening, watching, or brushing their teeth).  Coming soon.

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