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29 August 2016

A letter to my forthcoming AP Physics 1 class

School starts for me in a couple of days.  I've got a wonderful first-world problem to deal with: I have more students signed up for my AP Physics 1-equivalent course than I have desks in my very large classroom.  

We're going to eventually deal with this issue by moving in more desks.  But first, I want to be sure that these prospective students know what they're getting into.  I'm more than willing to teach an enormous class -- as long as everyone in the class is there for the right reasons.  

Below is a letter I've sent to everyone who's currently enrolled.  Note that I've attempted to communicate my personal excitement and investment in the material -- those of you who read my blog know all about that, but students who don't know me well aren't familiar with my eccentricities.  See the part where I reassure both first-time and second-time physics students that this course is for them.  No calculus nor previous physics required, though previous physics doesn't mean you'll be bored.

And finally, note the direct approach to issues of mindset, pedagogy, and reasons for enrolling.  I've heard from large numbers of good physics teachers who are similarly direct and transparent with their classes, especially because AP Physics 1 is so fundamentally different from most any class my students have ever taken before.The advice I got was, manage expectations, plea repeatedly for students to have patience with me and with themselves... and then I'll be likely to have a great and exciting year because success will come sooner than the students expect rather than later.


Hey, all... I have you signed up for Honors Physics 1.   I wanted to give you some background information about what this class is all about.

The course itself is exciting, with lots of hands-on laboratory work.  You'll learn in tremendous depth the rules that govern how objects move, how circuits work, how waves propagate.  I've been studying physics for more than a quarter century, and I still discover new and exciting things each year.  Physics is the best.

Honors Physics 1 is a college-level introduction to physics.  We will prepare you to take the AP Physics 1 exam in early May -- based on past history, you're likely to do well, almost always well enough to earn college credit.  When you take an actual college physics course, your experience here will make you the natural leader of your class.  You'll be the one explaining physics to your friends, often with enthusiastic hand gestures and quick experiments that you make up on the spot.  

Now, that said, I'd like you to consider your reasons for taking this course.  Success in physics cannot be attained by merely "hard work".  You will need to enter into this year with a growth mindset, willing to dive headfirst into learning new skills.  Homework, test, and quiz problems will NOT be essentially identical to the ones we did in class; every physics problem represents a new situation, a new puzzle to be figured out.  We will do extensive experimental work, in which you will not be given a list of instructions, but rather a task to accomplish in a creative way.

Are you taking physics for the first time?  That's fantastic.  Though some members of the class will have taken conceptual physics previously, I assume that you have no prior knowledge of physics -- nor any mathematical skills beyond algebra 1.  Honors Physics 1 can be a perfect introduction to rigorous college physics.  By the end, you'll know exactly how to learn physics, such that you can advance to the next level of physics in college; or such that you acquire a serious background in the subject even if you know that you never want to take another physics class.  First-timers are in the right place.

Have you had conceptual or general physics before?  That's also fantastic.  We will cover some of the same topics you've already seen, but at a much deeper level conceptually, mathematically, and experimentally.  You'll get a chance to answer some of those burning "why" questions that your teacher told you were beyond the scope of your first course.  We'll talk about motion, force, energy, momentum, waves, and circuits, but also rotation and universal gravitation.  Honors Physics 1 can be a great follow-up that prepares you well for (or, on the contrary, can exempt you from) college physics.  Second-year physics students are also in the right place.

But please think carefully.  Are you taking this course mainly so that you can pad your college resume or your GPA?  Is a primary motive that honors physics will make your transcript more impressive?  That you're more likely to advance your GPA above some target if you're in an additional honors course?  If so, this is definitely not the course for you.  It's not that my students' grades are ever really bad -- most everyone tends to get As and Bs, with Cs rare.  It's that if you're not exited about and intrinsically interested in the course content, the effort necessary to earn those grades will not be worth it.  You'll find yourself angry and resentful at a subject that can't be conquered by sheer force of will.

Think how you will react when a test asks you about kind of situation or experiment that you've never seen before in class.  If you'll say, "you didn't cover that, that's not fair, how did you expect us to know", this physics class is not for you.

But if you'll say, "cool, here's my best shot, I hope Mr. Jacobs lets us try this in lab next week to see whether I'm on the right track", then you are perfectly placed in honors physics.

I'm always ready to talk about physics.  Feel free to call or email.

Thanks!  Can't wait to do some physics on Wednesday.


19 August 2016

The five-foot rule: one approach to encouraging effective collaboration

We all want our students to collaborate effectively on problems.  Problem is, there's a very fine line between working together to solve a difficult problem, on one hand; and simply copying another student's work, on the other.  And, no matter how obvious the difference may be to us, students don't necessarily get it.

It took me a while to learn about this disconnect between my own academic experience, my expectations, and those of my students.  At a previous school I became very frustrated and angry with students who seemed like they were copying each others' homework solutions.  And, they were copying, without question.  In their minds, though, they were merely reporting together the results of their effective collaboration -- that same collaboration that I had encouraged so strongly.  So they weren't happy with me for being unhappy with them for following my own instructions.  If you follow.  

The most important step I took toward resolving this difference of understanding was to re-cast the issue so it wasn't about academic integrity.  I couldn't say "don't copy and don't cheat" if the students and I had such good-faith but widely varying ideas of the definitions of "copy" and "cheat."  Rather, I had to find a way to give clear guidance to define the line between collaboration and copying, without invoking the emotionally charged language of academic integrity.

What I came up with, and what has served me well for decades now, was the Five Foot Rule.  My syllabus states*: 

The Five-Foot Rule
We encourage students to help each other.  You may even verbally guide a friend step-by-step through his solution to a problem.  However, do not under any circumstances just give someone your solution “to look at later”.  A friend may, in your presence, look briefly at your work to start himself in the right direction, but no one should ever be using another student’s written solution as a detailed reference.

Thus, when you are actually writing something to be turned in, you must be located at least five feet from any other physics student.  Do not do your homework while sitting next to someone; rather, sit well apart from one another in a dorm or conference room; or, have a discussion, then separate yourselves to write up your solution.

* Remember, I teach at a boys' school, so my use of gendered language is deliberate.  Please don't flame me.

Students who obey the five-foot rule are hardly likely to be copying, unless they have x-ray vision.  The point is for all students to explain the result of collaborative discussion in their own words.  

Then, when inevitably you find two identical problem sets, you can avoid making accusations of dishonesty or cheating.  You can simply discuss the obvious violation of the five-foot rule, and ask that this rule be adhered to.  If the violations continue, and you have to get parents or administrators involved, you are likely to get support.  

Accusations of cheating or copying carry harsh implications. Parents instinctively defend their children, logic be damned.  Administrators question whether it's worth their political capital to engage in a fight over small-scale homework copying -- especially when you expressly encouraged collaboration!

But you're not accusing anyone of cheating, no, not at all.  You're merely asking for cooperation in enforcing and adhering to a straightforward class rule.  Just as students are expected to treat laboratory equipment carefully, just as they're expected to show up on time with their homework finished, they're expected to sit five feet from anyone else when they write work to be turned in.  That's a reasonable enough procedure to follow that students look like idiots if they protest. 

So they don't protest.  And they follow the rule.  And so they do their own work... often with help, often by rephrasing what a friend told them.  But that's fine -- rewriting in one's own words is a significant step toward deep understanding.

10 August 2016

Secret to AP Physics 1: Build *gradually* from calculations to verbal-response

Last year, I swore a blood oath that I would never teach juniors and seniors again.  I loved so much my 9th graders' growth mindsets, their puppyish enthusiasm, their enduring trust in an expert teacher who cared about them.  I could not have been happier teaching the conceptual and the AP 9th grade course.

Well, um... sometimes the Patriots need Troy Brown to switch from reciever to defensive back; sometimes the Yankees need Alex Rodriguez to play third base rather than his natural shortstop.  And, needs must in the physics department, too.  I've gotta pick up the junior-senior AP Physics 1 class this year.  Unless I'm mercifully struck by lightning for breaking my blood oath, anyway.

The good news is, I've made and learned from a bunch of mistakes in teaching this course a couple of years ago.  See the series of three posts (starting here) from April 2015.  

You've heard over and over that AP Physics 1 requires deep understanding and verbal reasoning.  I've told you, the College Board has told you.  The released free response require zero -- ZERO! -- numerical calculations over four exams.

Yet, my problem sets through the first several months require calculations.  My first test in September is constructed based on old AP Physics B items, which require numerical calculation.  Even my mid-February test includes two Physics B-style free response questions along with a paragraph response item.

Of course, these problem set and test items are hardly just "find the right equation and plug in numbers" questions.  They include "justify your answer" parts, qualitative-quantitative translation, "explain what would change", and all sorts of questions that probe understanding beyond just calculation.  But they start with calculation.  Why?

Because I learned the hard way how fixed-mindset juniors and seniors approach this new and intimidating subject.

My students are used to math class, where the method is subordinate to the answer.  Explaining how to solve a problem is less important than clever use of various routines to get to the answer.  The test of whether a problem is done sufficiently is simple -- compare the student's answer to the teacher's or textbook's answer.  Black and white, right or wrong.

Yet, in their writing classes, much is negotiable.  Style is personal, both to the student and the teacher.  Is this piece of literature referencing Homer's Oddyssey?  Very likely a clever student can make a resonable argument, however tortured, which will -- if phrased with good grammar and big words -- earn high marks.*  My wife the English teacher tells of pointing students to clear rules in grammar books, only for the students to tell her that the rule doesn't apply to their particular paper, or that the rule itself is wrong.

* The teacher may give these high marks as much to avoid the inevitable protracted lawyerly discussions about why the marks should have been higher as because the paper actually deserved high marks.

The skills required for AP Physics 1 are far closer to those used in English than in math.  A problem is similar to a page-long essay.  The explanation is as important as the conclusion itself, as is demonstrated by the released free-response rubrics which award little credit for answers in the absence of clear justification.

And therefore, veteran students revert to English class mode.  I can't tell you how many quasi-confrontations I had with upperclassmen:  

"What's wrong with this answer?"  

"Well, as we discussed in class, you've gotta connect the conclusion that the distance increases to the fact that the mass is in the denominator with all else constant, and thus is inversely related to distance." 

"I said that."  

"No, you just said 'distance increases because of the mass.'"  You have to explain the connection between mass and distance with reference to the relevant equation."

"Yeah, I know, that's what I did.  Now what's wrong with that?"

"Who's on first?"

Start the year with calculation in order to avoid these frustrating converstaions; and in order to build the skills that will allow for better and better explanations throughout the year.  When I assign calculational questions, no one ever asks "what's wrong with this answer?"  They know: the numerical result doesn't match my numerical result.  Instead, they ask, why didn't I get the right answer?  That discussion is usually extremely productive.  And, I can follow up those discussions with a targeted quiz question about how a common error led to a wrong answer.  

Point is, instead of blaming me for their own inadequacies, students who get numerical calculation questions wrong tend to be willing to hear about the source of their own misunderstanding.  The process of correcting their work, of identifiying common errors, teaches the very skills that AP 1 demands.

By March, I can give exclusively AP Physics 1 items, with no calculations whatsoever.  That's because I've weaned the class off of numbers as a crutch, or of numbers as a way to avoid an unproductive argument about points.  After months of exposure to physics problem solving and laboratory work, my students understand the point: not to earn points, not even to get the right answer... but to explain how the natural world works based on the facts and relationships we've studied.